diff --git a/src/aioice/ice.py b/src/aioice/ice.py
index 45a1a75..b8c4b8c 100644
--- a/src/aioice/ice.py
+++ b/src/aioice/ice.py
@@ -382,7 +382,7 @@ def remote_candidates(self) -> List[Candidate]:
         """
         return self._remote_candidates[:]
 
-    async def add_remote_candidate(self, remote_candidate: Candidate) -> None:
+    async def add_remote_candidate(self, remote_candidate: Optional[Candidate]) -> None:
         """
         Add a remote candidate or signal end-of-candidates.