diff --git a/readpass.c b/readpass.c
index 33fc03bb7..b3e799036 100644
--- a/readpass.c
+++ b/readpass.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: readpass.c,v 1.55 2019/11/12 22:34:20 djm Exp $ */
+/* $OpenBSD: readpass.c,v 1.56 2019/11/12 22:35:02 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -75,6 +75,7 @@ ssh_askpass(char *askpass, const char *msg)
 		close(p[0]);
 		if (dup2(p[1], STDOUT_FILENO) == -1)
 			fatal("ssh_askpass: dup2: %s", strerror(errno));
+		setenv("SSH_ASKPASS_PROMPT", "confirm", 1); /* hint to UI */
 		execlp(askpass, askpass, msg, (char *)NULL);
 		fatal("ssh_askpass: exec(%s): %s", askpass, strerror(errno));
 	}