diff --git a/jquery.mjs.nestedSortable.js b/jquery.mjs.nestedSortable.js
index f04f21e..6b5ff77 100644
--- a/jquery.mjs.nestedSortable.js
+++ b/jquery.mjs.nestedSortable.js
@@ -267,6 +267,12 @@
 			      	vertical: this._getDragVerticalDirection(),
 				horizontal: this._getDragHorizontalDirection()
 		    	};
+
+			// fix for jquery-ui 1.13+
+			this.dragDirection = {
+				vertical: this._getDragVerticalDirection(),
+				horizontal: this._getDragHorizontalDirection()
+			};
 			
 			//Rearrange
 			for (i = this.items.length - 1; i >= 0; i--) {