diff --git a/zuul.d/pipelines.yaml b/zuul.d/pipelines.yaml
index 04f2361388..9e9b16cf01 100644
--- a/zuul.d/pipelines.yaml
+++ b/zuul.d/pipelines.yaml
@@ -124,6 +124,10 @@
         - event: comment-added
           approval:
             - Allow-Post-Review: [1]
+    # Require all changes enqueued to this pipeline originate from Gerrit
+    # including those used as depends on. This ensures the requirement defined
+    # above is always set.
+    allow-other-connections: false
 
 - pipeline:
     name: post