diff --git a/virtualmin-install.sh b/virtualmin-install.sh
index 696b999..984e476 100644
--- a/virtualmin-install.sh
+++ b/virtualmin-install.sh
@@ -140,6 +140,15 @@ while [ "$1" != "" ]; do
   esac
 done
 
+# Force setup mode, if script name is `setup-repos.sh` as it
+# is used by Virtualmin API, to make sure users won't run an
+# actuall install script under any circumstances
+if [ "${0##*/}" = "setup-repos.sh" ]; then
+  setup_only=1
+  mode='setup'
+  unstable='unstable'
+fi
+
 # Store new log each time
 log="$pwd/$log_type.log"
 if [ -e "$log" ]; then