diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2963e7f..e7f3fe8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 * Implement functionality for editing mediated request. Refs UIREQMED-22.
 * *BREAKING* Migrate to new `mod-circulation-bff` endpoints. Refs UIREQMED-39.
 * Add circulation-storage.staff-slips.collection.get for get staff-slips on Send item in transit. Refs UIREQMED-55.
+* Add Decline Action for Mediated request with status of New - Awaiting confirmation. Refs UIREQMED-42.
 
 ## [1.1.0](https://github.com/folio-org/ui-requests-mediated/tree/v1.1.0) (2024-10-30)
 * Update github actions. Refs UIREQMED-14.
diff --git a/package.json b/package.json
index 7239fad..e6d0acf 100644
--- a/package.json
+++ b/package.json
@@ -171,7 +171,7 @@
         ],
         "subPermissions": [
           "ui-requests-mediated.view",
-          "requests-mediated.mediated-request.item.delete"
+          "requests-mediated.decline-mediated-request.execute"
         ],
         "visible": true
       },
diff --git a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.js b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.js
index 8c4ac08..2ccb532 100644
--- a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.js
+++ b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.js
@@ -1,3 +1,6 @@
+import {
+  useState,
+} from 'react';
 import PropTypes from 'prop-types';
 import {
   useHistory,
@@ -14,6 +17,7 @@ import {
 import {
   IfPermission,
   TitleManager,
+  useOkapiKy,
 } from '@folio/stripes/core';
 import {
   Button,
@@ -31,6 +35,7 @@ import TitleInformation from '../TitleInformation';
 import MediatedRequestInformation from '../MediatedRequestInformation';
 import ItemDetail from '../ItemDetail';
 import UserDetail from '../UserDetail';
+import DeclineModal from './components/DeclineModal';
 import {
   useMediatedRequestById,
   useUserById,
@@ -52,6 +57,7 @@ import {
   getPatronGroup,
   getUserPreferences,
   getReferredRecordData,
+  confirmDeclineModal,
 } from '../../../../utils';
 
 const DETAIL_PANE_WIDTH = '44%';
@@ -64,15 +70,19 @@ const MediatedRequestsDetail = ({
   stripes,
   patronGroups,
   setRequest,
+  updateMediatedRequestList,
 }) => {
   const history = useHistory();
   const location = useLocation();
+  const ky = useOkapiKy();
   const mediatedRequestIdFromPathname = location.pathname.substring(location.pathname.lastIndexOf('/') + 1);
 
   const { formatMessage } = useIntl();
   const {
     mediatedRequest,
     isFetching,
+    shouldUpdateMediatedRequestById,
+    setShouldUpdateMediatedRequestById,
   } = useMediatedRequestById(mediatedRequestIdFromPathname);
   const { userData } = useUserById(mediatedRequest?.requesterId, isFetching);
   const { servicePoints } = useServicePoints();
@@ -80,6 +90,20 @@ const MediatedRequestsDetail = ({
 
   setRequest(mediatedRequest);
 
+  const [declineModalOpen, setDeclineModalOpen] = useState(false);
+  const onOpenDeclineModal = () => setDeclineModalOpen(true);
+  const declineModalState = {
+    shouldUpdateMediatedRequestById,
+    setShouldUpdateMediatedRequestById,
+    setDeclineModalOpen,
+  };
+  const declineModalProps = {
+    ky,
+    url: `requests-mediated/mediated-requests/${mediatedRequestIdFromPathname}/decline`,
+    updateMediatedRequestList,
+  };
+  const onConfirmDeclineModal = () => confirmDeclineModal(declineModalState, declineModalProps);
+  const onCloseDeclineModal = () => setDeclineModalOpen(false);
   const isActionMenuVisible = () => (
     get(mediatedRequest, MEDIATED_REQUESTS_RECORD_FIELD_PATH[MEDIATED_REQUESTS_RECORD_FIELD_NAME.STATUS], DEFAULT_VIEW_VALUE) === MEDIATED_REQUEST_STATUS.NEW_AWAITING_CONFIRMATION
       ? stripes.hasPerm('ui-requests-mediated.requests-mediated.view-confirm.execute') || stripes.hasPerm('ui-requests-mediated.requests-mediated.view-create-edit.execute') || stripes.hasPerm('ui-requests-mediated.requests-mediated.view-decline.execute')
@@ -96,6 +120,10 @@ const MediatedRequestsDetail = ({
       onToggle();
       history.push(`${mediatedRequestsActivitiesUrl}/edit/${mediatedRequestIdFromPathname}`);
     };
+    const handleDecline = () => {
+      onOpenDeclineModal();
+      onToggle();
+    };
 
     return (
       <>
@@ -114,7 +142,7 @@ const MediatedRequestsDetail = ({
           <Button
             buttonStyle="dropdownItem"
             marginBottom0
-            onClick={onToggle}
+            onClick={handleDecline}
           >
             <Icon icon={ICONS.TIMES_CIRCLE}>
               <FormattedMessage id="ui-requests-mediated.mediatedRequestDetails.actionMenu.decline" />
@@ -218,6 +246,12 @@ const MediatedRequestsDetail = ({
                   hideAssignButton
                 />
               </AccordionStatus>
+              <DeclineModal
+                open={declineModalOpen}
+                title={get(mediatedRequest, MEDIATED_REQUESTS_RECORD_FIELD_PATH[MEDIATED_REQUESTS_RECORD_FIELD_NAME.TITLE], DEFAULT_VIEW_VALUE)}
+                onConfirm={onConfirmDeclineModal}
+                onClose={onCloseDeclineModal}
+              />
             </>
       }
     </Pane>
@@ -227,6 +261,7 @@ const MediatedRequestsDetail = ({
 MediatedRequestsDetail.propTypes = {
   stripes: PropTypes.object.isRequired,
   setRequest: PropTypes.func.isRequired,
+  updateMediatedRequestList: PropTypes.func.isRequired,
   patronGroups: PropTypes.arrayOf(PropTypes.shape({
     id: PropTypes.string,
     group: PropTypes.string,
diff --git a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.test.js b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.test.js
index 51544e9..57520aa 100644
--- a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.test.js
+++ b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/MediatedRequestsDetail.test.js
@@ -57,6 +57,8 @@ const labelIds = {
   requesterAccordion: 'ui-requests-mediated.mediatedRequestDetail.requester.accordionLabel',
   noItemInformation: 'ui-requests-mediated.mediatedRequestDetail.item.noInformation',
   editAndConfirmButton: 'ui-requests-mediated.mediatedRequestDetails.actionMenu.editAndConfirm',
+  declineButton: 'ui-requests-mediated.mediatedRequestDetails.actionMenu.decline',
+  declineModalTitle: 'ui-requests-mediated.declineModal.title',
 };
 
 describe('MediatedRequestsDetail', () => {
@@ -349,5 +351,11 @@ describe('MediatedRequestsDetail', () => {
 
       expect(push).toHaveBeenCalledWith(`${getMediatedRequestsActivitiesUrl()}/edit/id`);
     });
+
+    it('should render "Decline" button', () => {
+      const declineButton = screen.getByText(labelIds.declineButton);
+
+      expect(declineButton).toBeInTheDocument();
+    });
   });
 });
diff --git a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.js b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.js
new file mode 100644
index 0000000..754ceaf
--- /dev/null
+++ b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.js
@@ -0,0 +1,57 @@
+import PropTypes from 'prop-types';
+import { FormattedMessage } from 'react-intl';
+import {
+  Button,
+  Modal,
+  ModalFooter,
+} from '@folio/stripes/components';
+
+const DeclineModal = ({
+  open,
+  title,
+  onConfirm,
+  onClose,
+}) => {
+  const footer = (
+    <ModalFooter>
+      <Button
+        data-testid="confirmButton"
+        buttonStyle="primary"
+        onClick={onConfirm}
+      >
+        <FormattedMessage id="ui-requests-mediated.declineModal.confirm" />
+      </Button>
+      <Button
+        data-testid="backButton"
+        onClick={onClose}
+      >
+        <FormattedMessage id="ui-requests-mediated.declineModal.back" />
+      </Button>
+    </ModalFooter>
+  );
+
+  return (
+    <Modal
+      dismissible
+      label={<FormattedMessage id="ui-requests-mediated.declineModal.title" />}
+      open={open}
+      size="small"
+      footer={footer}
+      onClose={onClose}
+    >
+      <FormattedMessage
+        id="ui-requests-mediated.declineModal.message"
+        values={{ title }}
+      />
+    </Modal>
+  );
+};
+
+DeclineModal.propTypes = {
+  open: PropTypes.bool.isRequired,
+  title: PropTypes.string.isRequired,
+  onConfirm: PropTypes.func.isRequired,
+  onClose: PropTypes.func.isRequired,
+};
+
+export default DeclineModal;
diff --git a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.test.js b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.test.js
new file mode 100644
index 0000000..113b513
--- /dev/null
+++ b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/DeclineModal.test.js
@@ -0,0 +1,76 @@
+import {
+  render,
+  screen,
+  fireEvent,
+} from '@folio/jest-config-stripes/testing-library/react';
+
+import DeclineModal from './DeclineModal';
+
+const testIds = {
+  confirmButton: 'confirmButton',
+  backButton: 'backButton',
+};
+const messageIds = {
+  title: 'ui-requests-mediated.declineModal.title',
+  message: 'ui-requests-mediated.declineModal.message',
+  confirmButton: 'ui-requests-mediated.declineModal.confirm',
+  backButton: 'ui-requests-mediated.declineModal.back',
+};
+const defaultProps = {
+  open: true,
+  title: 'Title',
+  onConfirm: jest.fn(),
+  onClose: jest.fn(),
+};
+
+describe('DeclineModal', () => {
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  beforeEach(() => {
+    render(
+      <DeclineModal {...defaultProps} />
+    );
+  });
+
+  it('should render title', () => {
+    expect(screen.getByText(messageIds.title)).toBeVisible();
+  });
+
+  it('should render message', () => {
+    expect(screen.getByText(messageIds.message)).toBeVisible();
+  });
+
+  describe('Confirm button', () => {
+    it('should render confirm button', () => {
+      expect(screen.getByTestId(testIds.confirmButton)).toBeVisible();
+    });
+
+    it('should render confirm button text', () => {
+      expect(screen.getByText(messageIds.confirmButton)).toBeVisible();
+    });
+
+    it('should call onConfirm', () => {
+      fireEvent.click(screen.getByTestId(testIds.confirmButton));
+
+      expect(defaultProps.onConfirm).toHaveBeenCalled();
+    });
+  });
+
+  describe('Back button', () => {
+    it('should render back button', () => {
+      expect(screen.getByTestId(testIds.backButton)).toBeVisible();
+    });
+
+    it('should render back button text', () => {
+      expect(screen.getByText(messageIds.backButton)).toBeVisible();
+    });
+
+    it('should call onClose', () => {
+      fireEvent.click(screen.getByTestId(testIds.backButton));
+
+      expect(defaultProps.onClose).toHaveBeenCalled();
+    });
+  });
+});
diff --git a/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/index.js b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/index.js
new file mode 100644
index 0000000..9faba9e
--- /dev/null
+++ b/src/components/MediatedRequestsActivities/components/MediatedRequestsDetail/components/DeclineModal/index.js
@@ -0,0 +1 @@
+export { default } from './DeclineModal';
diff --git a/src/hooks/useMediatedRequestById/useMediatedRequestById.js b/src/hooks/useMediatedRequestById/useMediatedRequestById.js
index 16e4e03..8fe42a5 100644
--- a/src/hooks/useMediatedRequestById/useMediatedRequestById.js
+++ b/src/hooks/useMediatedRequestById/useMediatedRequestById.js
@@ -1,3 +1,7 @@
+import {
+  useState,
+} from 'react';
+
 import { useQuery } from 'react-query';
 
 import {
@@ -6,13 +10,15 @@ import {
 } from '@folio/stripes/core';
 
 const useMediatedRequestById = (mediatedRequestId) => {
+  const [shouldUpdateMediatedRequestById, setShouldUpdateMediatedRequestById] = useState(0);
+
   const ky = useOkapiKy();
   const [namespace] = useNamespace({ key: 'mediatedRequest' });
   const {
     data,
     isFetching,
   } = useQuery(
-    [namespace, mediatedRequestId],
+    [namespace, mediatedRequestId, shouldUpdateMediatedRequestById],
     () => ky.get(`requests-mediated/mediated-requests/${mediatedRequestId}`).json(),
     { enabled: Boolean(mediatedRequestId) },
   );
@@ -20,6 +26,8 @@ const useMediatedRequestById = (mediatedRequestId) => {
   return {
     isFetching,
     mediatedRequest: data,
+    shouldUpdateMediatedRequestById,
+    setShouldUpdateMediatedRequestById,
   };
 };
 
diff --git a/src/routes/MediatedRequestsActivitiesContainer.js b/src/routes/MediatedRequestsActivitiesContainer.js
index b983827..91b4f17 100644
--- a/src/routes/MediatedRequestsActivitiesContainer.js
+++ b/src/routes/MediatedRequestsActivitiesContainer.js
@@ -39,6 +39,21 @@ export const buildQuery = (queryParams, pathComponents, resourceData, logger, pr
   return getCql(queryParams, pathComponents, resourceData, logger, props);
 };
 
+export const updateMediatedRequestList = (source, props) => {
+  const {
+    location,
+    history,
+  } = props;
+  const {
+    resources: {
+      query,
+    },
+  } = source;
+  const url = buildUrl(location, query);
+
+  history.push(url);
+};
+
 class MediatedRequestsActivitiesContainer extends React.Component {
   static manifest = Object.freeze({
     query: {
@@ -62,6 +77,7 @@ class MediatedRequestsActivitiesContainer extends React.Component {
           query: buildQuery,
         },
       },
+      resourceShouldRefresh: true,
       throwErrors: false,
     },
     reportRecords: {
@@ -161,6 +177,10 @@ class MediatedRequestsActivitiesContainer extends React.Component {
     }
   };
 
+  updateMediatedRequestList = () => {
+    updateMediatedRequestList(this.source, this.props);
+  };
+
   render() {
     if (this.source) {
       this.source.update(this.props, MEDIATED_REQUESTS_RECORDS_NAME);
@@ -176,7 +196,13 @@ class MediatedRequestsActivitiesContainer extends React.Component {
         mutator={this.props.mutator}
         settings={this.props.settings}
       >
-        {this.props.children}
+        {
+          React.Children.map(
+            this.props.children, child => React.cloneElement(child, {
+              updateMediatedRequestList: this.updateMediatedRequestList,
+            })
+          )
+        }
       </MediatedRequestsActivities>
     );
   }
diff --git a/src/routes/MediatedRequestsActivitiesContainer.test.js b/src/routes/MediatedRequestsActivitiesContainer.test.js
index 1bc9ee5..eea5c67 100644
--- a/src/routes/MediatedRequestsActivitiesContainer.test.js
+++ b/src/routes/MediatedRequestsActivitiesContainer.test.js
@@ -6,6 +6,7 @@ import userEvent from '@folio/jest-config-stripes/testing-library/user-event';
 
 import MediatedRequestsActivitiesContainer, {
   buildQuery,
+  updateMediatedRequestList,
 } from './MediatedRequestsActivitiesContainer';
 import MediatedRequestsActivities from '../components/MediatedRequestsActivities';
 
@@ -70,6 +71,9 @@ const props = {
       pathname: '',
     },
   },
+  history: {
+    push: jest.fn(),
+  },
   stripes: {
     logger,
   },
@@ -118,3 +122,19 @@ describe('buildQuery', () => {
     ));
   });
 });
+
+describe('updateMediatedRequestList', () => {
+  const source = {
+    resources: {
+      query: ['query=Test'],
+    },
+  };
+
+  it('should trigger history push', () => {
+    updateMediatedRequestList(source, props);
+
+    expect(props.history.push).toHaveBeenCalledWith(expect.stringContaining(
+      'query%3DTest'
+    ));
+  });
+});
diff --git a/src/utils.js b/src/utils.js
index 593b537..b148b7f 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -378,6 +378,29 @@ export const handleConfirmItemSubmit = async (itemBarcode, confirmItemState, con
     });
 };
 
+export const confirmDeclineModal = (declineModalState, declineModalProps) => {
+  const {
+    shouldUpdateMediatedRequestById,
+    setShouldUpdateMediatedRequestById,
+    setDeclineModalOpen,
+  } = declineModalState;
+  const {
+    ky,
+    url,
+    updateMediatedRequestList,
+  } = declineModalProps;
+
+  ky.post(url)
+    .then(() => {
+      updateMediatedRequestList();
+      setShouldUpdateMediatedRequestById(shouldUpdateMediatedRequestById + 1);
+      setDeclineModalOpen(false);
+    })
+    .catch(() => {
+      setDeclineModalOpen(false);
+    });
+};
+
 export const getStaffSlipsTemplateByType = (staffSlips = [], slipType = STAFF_SLIPS_TYPE.TRANSIT_MEDIATED_REQUESTS) => {
   const slipTypeInLowerCase = slipType.toLowerCase();
   const slipTemplate = staffSlips.find(slip => slip.name.toLowerCase() === slipTypeInLowerCase);
diff --git a/src/utils.test.js b/src/utils.test.js
index c1bae09..a2ee397 100644
--- a/src/utils.test.js
+++ b/src/utils.test.js
@@ -48,6 +48,7 @@ import {
   getDeliveryAddressForCsvRecords,
   modifyRecordsToExport,
   handleConfirmItemSubmit,
+  confirmDeclineModal,
   getStaffSlipsTemplateByType,
   escapeValue,
   buildTemplate,
@@ -1009,6 +1010,59 @@ describe('handleConfirmItemSubmit', () => {
   });
 });
 
+describe('confirmDeclineModal', () => {
+  const ky = {
+    post: jest.fn().mockImplementation(() => Promise.resolve()),
+  };
+  const declineModalState = {
+    shouldUpdateMediatedRequestById: 0,
+    setShouldUpdateMediatedRequestById: jest.fn(),
+    setDeclineModalOpen: jest.fn(),
+  };
+  const declineModalProps = {
+    ky,
+    url: 'requests-mediated/mediated-requests/111/decline',
+    updateMediatedRequestList: jest.fn(),
+  };
+
+  it('should trigger "ky.post" with correct props', () => {
+    confirmDeclineModal(declineModalState, declineModalProps);
+
+    expect(ky.post).toHaveBeenCalledWith(declineModalProps.url);
+  });
+
+  it('should trigger "updateMediatedRequestList" on success', () => {
+    confirmDeclineModal(declineModalState, declineModalProps);
+
+    expect(declineModalProps.updateMediatedRequestList).toHaveBeenCalled();
+  });
+
+  it('should trigger "setShouldUpdateMediatedRequestById" on success', () => {
+    confirmDeclineModal(declineModalState, declineModalProps);
+
+    expect(declineModalState.setShouldUpdateMediatedRequestById).toHaveBeenCalledWith(1);
+  });
+
+  it('should trigger "setDeclineModalOpen" on success', () => {
+    confirmDeclineModal(declineModalState, declineModalProps);
+
+    expect(declineModalState.setDeclineModalOpen).toHaveBeenCalledWith(false);
+  });
+
+  it('should trigger "setDeclineModalOpen" on errors', () => {
+    const declineModalPropsWithErrors = {
+      ...declineModalProps,
+      ky: {
+        post: jest.fn().mockImplementation(() => Promise.reject()),
+      },
+    };
+
+    confirmDeclineModal(declineModalState, declineModalPropsWithErrors);
+
+    expect(declineModalState.setDeclineModalOpen).toHaveBeenCalledWith(false);
+  });
+});
+
 describe('getStaffSlipsTemplateByType', () => {
   const slipTypeName = STAFF_SLIPS_TYPE.TRANSIT_MEDIATED_REQUESTS;
   const slipTypeTemplate = <p>${slipTypeName}</p>;
diff --git a/translations/ui-requests-mediated/en.json b/translations/ui-requests-mediated/en.json
index c18d55a..5e328b3 100644
--- a/translations/ui-requests-mediated/en.json
+++ b/translations/ui-requests-mediated/en.json
@@ -34,6 +34,11 @@
   "confirmItem.errorModal.sendItemInTransit.message": "No \"Send item in transit\" transaction could be found for this item",
   "confirmItem.errorModal.close": "Close",
 
+  "declineModal.title": "Confirm Mediated request decline",
+  "declineModal.message": "<b>{title}</b> will be <b>declined</b>",
+  "declineModal.confirm": "Confirm",
+  "declineModal.back": "Back",
+
   "confirmItemList.columnName.arrivalDate": "Arrival date",
   "confirmItemList.columnName.inTransitDate": "In transit date",
   "confirmItemList.columnName.title": "Title",