diff --git a/server/src/main/java/org/elasticsearch/search/aggregations/bucket/terms/InternalMappedSignificantTerms.java b/server/src/main/java/org/elasticsearch/search/aggregations/bucket/terms/InternalMappedSignificantTerms.java
index c0d7103e42e8e..0b09ad3d3d85e 100644
--- a/server/src/main/java/org/elasticsearch/search/aggregations/bucket/terms/InternalMappedSignificantTerms.java
+++ b/server/src/main/java/org/elasticsearch/search/aggregations/bucket/terms/InternalMappedSignificantTerms.java
@@ -71,8 +71,9 @@ protected final void writeTermTypeInfoTo(StreamOutput out) throws IOException {
     }
 
     @Override
+    @SuppressWarnings({ "rawtypes", "unchecked" })
     public Iterator<SignificantTerms.Bucket> iterator() {
-        return buckets.stream().map(bucket -> (SignificantTerms.Bucket) bucket).toList().iterator();
+        return (Iterator) buckets.iterator();
     }
 
     @Override