@@ -5,6 +5,7 @@ import type {
 	HTMLAttributes,
 	PointerEvent,
 } from 'react';
+import { speak } from '@wordpress/a11y';
 import { ResizableBox } from '@wordpress/components';
 import { useState } from '@wordpress/element';
 import { _n, sprintf } from '@wordpress/i18n';
@@ -106,10 +107,24 @@ export function GridRowResizer( { clientId }: GridRowResizerProps ) {
 				} }
 				onResizeStop={ ( _event, direction, _element, delta ) => {
 					setResize( null );
-					resizeRows(
+					const rowCount = resizeRows(
 						direction as Edge,
 						getRowDelta( delta.height )
 					);
+					// The row count label is only shown while resizing.
+					if ( rowCount ) {
+						speak(
+							sprintf(
+								/* translators: %d: Number of rows in a grid. */
+								_n(
+									'The grid now has %d row.',
+									'The grid now has %d rows.',
+									rowCount
+								),
+								rowCount
+							)
+						);
+					}
 				} }
 			>
 				{ resize && (
 
@@ -14,9 +14,10 @@ interface ResizeGridRows {
 	 */
 	getRowCount: ( edge: GridEdge, rowDelta: number ) => number;
 	/**
-	 * Applies a resize.
+	 * Applies a resize, and gives the new row count, or `undefined` when
+	 * nothing changes.
 	 */
-	resizeRows: ( edge: GridEdge, rowDelta: number ) => void;
+	resizeRows: ( edge: GridEdge, rowDelta: number ) => number | undefined;
 }
 
 /**
@@ -27,7 +28,7 @@ interface ResizeGridRows {
  *
  * @param gridClientId Client ID of the grid.
  *
- * @return `getRowCount` gives the row count a resize would lead to, and `resizeRows` applies it.
+ * @return `getRowCount` gives the row count a resize would lead to, and `resizeRows` applies it and gives the new row count.
  */
 export function useResizeGridRows( gridClientId: string ): ResizeGridRows {
 	const registry = useRegistry();
@@ -60,17 +61,18 @@ export function useResizeGridRows( gridClientId: string ): ResizeGridRows {
 	const resizeRows = useCallback(
 		( edge: GridEdge, rowDelta: number ) => {
 			if ( ! rowDelta ) {
-				return;
+				return undefined;
 			}
-			const { updates } = getResize( edge, rowDelta );
+			const { rowCount, updates } = getResize( edge, rowDelta );
 			if ( ! updates ) {
-				return;
+				return undefined;
 			}
 			updateBlockAttributes(
 				Object.keys( updates ),
 				updates,
 				/* uniqueByBlock: */ true
 			);
+			return rowCount;
 		},
 		[ getResize, updateBlockAttributes ]
 	);