diff --git a/configure.ac b/configure.ac
index 2a16a18947..848c92f8fe 100644
--- a/configure.ac
+++ b/configure.ac
@@ -234,7 +234,7 @@ AC_SUBST(GSTPB_PREFIX)
 
 dnl GTK is optional and used in examples
 HAVE_GTK=no
-GT_REQ=3.0.0
+GTK_REQ=3.0.0
 if test "x$BUILD_EXAMPLES" = "xyes"; then
   PKG_CHECK_MODULES(GTK, gtk+-$with_gtk >= $GTK_REQ, HAVE_GTK=yes, HAVE_GTK=no)
   dnl some examples need gtk+-x11