diff --git a/support/scripts/br2-external b/support/scripts/br2-external
index b2bff644b6..1a0c743462 100755
--- a/support/scripts/br2-external
+++ b/support/scripts/br2-external
@@ -67,6 +67,12 @@ do_validate() {
     if [ ! -r "${br2_ext}" -o ! -x "${br2_ext}" ]; then
         error "'%s': permission denied\n" "${br2_ext}"
     fi
+    if [ ! -f "${br2_ext}/external.mk" ]; then
+        error "'%s/external.mk': no such file or directory\n" "${br2_ext}"
+    fi
+    if [ ! -f "${br2_ext}/Config.in" ]; then
+        error "'%s/Config.in': no such file or directory\n" "${br2_ext}"
+    fi
 
     BR2_EXT="$(cd "${br2_ext}"; pwd -P )"
 }