diff --git a/Makefile b/Makefile
index 5329cb26ab..f5d7536dd2 100644
--- a/Makefile
+++ b/Makefile
@@ -147,16 +147,11 @@ $(if $(BASE_DIR),, $(error output directory "$(O)" does not exist))
 # on the command line, therefore the file is re-created every time make is run.
 #
 # When BR2_EXTERNAL is set to an empty value (e.g. explicitly in command
-# line), the .br-external file is removed and we point to
-# support/dummy-external. This makes sure we can unconditionally include the
-# Config.in and external.mk from the BR2_EXTERNAL directory. In this case,
-# override is necessary so the user can clear BR2_EXTERNAL from the command
-# line, but the dummy path is still used internally.
+# line), the .br-external file is removed.
 
 BR2_EXTERNAL_FILE = $(BASE_DIR)/.br-external
 -include $(BR2_EXTERNAL_FILE)
 ifeq ($(BR2_EXTERNAL),)
-  override BR2_EXTERNAL = support/dummy-external
   $(shell rm -f $(BR2_EXTERNAL_FILE))
 else
   _BR2_EXTERNAL = $(shell cd $(BR2_EXTERNAL) >/dev/null 2>&1 && pwd)
@@ -165,6 +160,7 @@ else
   endif
   override BR2_EXTERNAL := $(_BR2_EXTERNAL)
   $(shell echo BR2_EXTERNAL ?= $(BR2_EXTERNAL) > $(BR2_EXTERNAL_FILE))
+  BR2_EXTERNAL_MK = $(BR2_EXTERNAL)/external.mk
 endif
 
 # To make sure that the environment variable overrides the .config option,
@@ -457,7 +453,8 @@ include boot/common.mk
 include linux/linux.mk
 include fs/common.mk
 
-include $(BR2_EXTERNAL)/external.mk
+# Nothing to include if no BR2_EXTERNAL tree in use
+include $(BR2_EXTERNAL_MK)
 
 # Now we are sure we have all the packages scanned and defined. We now
 # check for each package in the list of enabled packages, that all its
diff --git a/support/dummy-external/Config.in b/support/dummy-external/Config.in
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/support/dummy-external/external.mk b/support/dummy-external/external.mk
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/support/scripts/br2-external b/support/scripts/br2-external
index 6c2b85b5ca..1c42ffafc7 100755
--- a/support/scripts/br2-external
+++ b/support/scripts/br2-external
@@ -19,9 +19,11 @@ main() {
     # Forget options; keep only positional args
     shift $((OPTIND-1))
 
-    if [ ${#} -ne 1 ]; then
-        error "need exactly one br2-external tree to be specified\n"
+    # Accept 0 or 1 br2-external tree.
+    if [ ${#} -gt 1 ]; then
+        error "only zero or one br2-external tree allowed.\n"
     fi
+
     br2_ext="${1}"
 
     if [ -z "${ofile}" ]; then
@@ -38,6 +40,11 @@ main() {
 do_validate() {
     local br2_ext="${1}"
 
+    # No br2-external tree is valid
+    if [ -z "${br2_ext}" ]; then
+        return
+    fi
+
     if [ ! -d "${br2_ext}" ]; then
         error "'%s': no such file or directory\n" "${br2_ext}"
     fi
@@ -52,12 +59,17 @@ do_validate() {
 do_kconfig() {
     printf '#\n# Automatically generated file; DO NOT EDIT.\n#\n'
     printf '\n'
+
+    if [ -z "${BR2_EXT}" ]; then
+        printf '# No br2-external tree defined.\n'
+        return
+    fi
+
     printf 'config BR2_EXTERNAL\n'
     printf '\tstring\n'
     printf '\tdefault "%s"\n' "${BR2_EXT}"
     printf '\n'
     printf 'menu "User-provided options"\n'
-    printf '\tdepends on BR2_EXTERNAL != "support/dummy-external"\n'
     printf '\n'
     printf 'source "%s/Config.in"\n' "${BR2_EXT}"
     printf '\n'