diff --git a/src/Extension/CmsTwigExtension.php b/src/Extension/CmsTwigExtension.php
index d422e58..b049e4f 100644
--- a/src/Extension/CmsTwigExtension.php
+++ b/src/Extension/CmsTwigExtension.php
@@ -262,7 +262,7 @@ public function spaceless($value)
     public function cmsAsset($resource)
     {
         if ($this->markupMode) {
-            return $resource;
+            return '/' . $resource;
         }
 
         return $this->cmsBaseUrl . '/' . $resource;