diff --git a/src/Batch/BatchUrlGenerator.php b/src/Batch/BatchUrlGenerator.php
index 08d2294..128b9c4 100644
--- a/src/Batch/BatchUrlGenerator.php
+++ b/src/Batch/BatchUrlGenerator.php
@@ -175,6 +175,11 @@ class BatchUrlGenerator {
       }
       $url_object = Url::fromUserInput($custom_path['path'], ['absolute' => TRUE]);
 
+      // Do not include external paths.
+      if (!$url_object->isRouted()) {
+        continue;
+      }
+
       $path = $url_object->getInternalPath();
       if ($this->batchInfo['remove_duplicates'] && $this->pathProcessed($path)) {
         continue;