diff --git a/packages/block-library/src/comments/block.json b/packages/block-library/src/comments/block.json
index 9469917ef150d0..51a926b8178151 100644
--- a/packages/block-library/src/comments/block.json
+++ b/packages/block-library/src/comments/block.json
@@ -29,10 +29,5 @@
 		}
 	},
 	"editorStyle": "wp-block-comments-editor",
-	"style": [
-		"wp-block-post-comments",
-		"wp-block-buttons",
-		"wp-block-button"
-	],
 	"usesContext": [ "postId", "postType" ]
 }
diff --git a/packages/block-library/src/comments/index.php b/packages/block-library/src/comments/index.php
index 2922821142ddcf..bc44255fd3cf52 100644
--- a/packages/block-library/src/comments/index.php
+++ b/packages/block-library/src/comments/index.php
@@ -65,6 +65,7 @@ function render_block_core_comments_query_loop( $attributes, $content, $block )
 	$output             = ob_get_clean();
 
 	wp_enqueue_script( 'comment-reply' );
+	enqueue_legacy_post_comments_block_styles( $block->name );
 
 	return sprintf( '<div %1$s>%2$s</div>', $wrapper_attributes, $output );
 }
@@ -100,6 +101,27 @@ function comments_query_loop_block_form_defaults( $fields ) {
 }
 add_filter( 'comment_form_defaults', 'comments_query_loop_block_form_defaults' );
 
+/**
+ * Enqueues styles for the legacy `core/post-comments` block.
+ *
+ * @param string $block_name Name of the new block type.
+ */
+function enqueue_legacy_post_comments_block_styles( $block_name ) {
+	static $are_styles_enqueued = false;
+
+	if ( ! $are_styles_enqueued ) {
+		$handles = array(
+			'wp-block-post-comments',
+			'wp-block-buttons',
+			'wp-block-button',
+		);
+		foreach( $handles as $handle ) {
+			wp_enqueue_block_style( $block_name, array( 'handle' => $handle) );
+		}
+		$are_styles_enqueued = true;
+	}
+}
+
 /**
  * Renders the legacy `core/post-comments` block on the server.
  * It triggers a developer warning and then calls the renamed