diff --git a/lisp/mouse.el b/lisp/mouse.el
index 5eeee1ec52..c165e1b0d2 100644
--- a/lisp/mouse.el
+++ b/lisp/mouse.el
@@ -1740,7 +1740,7 @@ mouse-drag-secondary
       (let (event end end-point)
 	(track-mouse
 	  (while (progn
-		   (setq event (read-event))
+		   (setq event (read-key))
 		   (or (mouse-movement-p event)
 		       (memq (car-safe event) '(switch-frame select-window))))