diff --git a/src/wp-includes/interactivity-api/class-wp-interactivity-api.php b/src/wp-includes/interactivity-api/class-wp-interactivity-api.php
index eab85e6b361da..1f4c5aeb9efba 100644
--- a/src/wp-includes/interactivity-api/class-wp-interactivity-api.php
+++ b/src/wp-includes/interactivity-api/class-wp-interactivity-api.php
@@ -1031,6 +1031,19 @@ private function data_wp_router_region_processor( WP_Interactivity_API_Directive
 		if ( 'enter' === $mode && ! $this->has_processed_router_region ) {
 			$this->has_processed_router_region = true;
 
+			// Initialize the `core/router` store.
+			$this->state(
+				'core/router',
+				array(
+					'navigation' => array(
+						'texts' => array(
+							'loading' => __( 'Loading page, please wait.' ),
+							'loaded'  => __( 'Page Loaded.' ),
+						),
+					),
+				)
+			);
+
 			// Enqueues as an inline style.
 			wp_register_style( 'wp-interactivity-router-animations', false );
 			wp_add_inline_style( 'wp-interactivity-router-animations', $this->get_router_animation_styles() );