diff --git a/src/anyio/_backends/_asyncio.py b/src/anyio/_backends/_asyncio.py
index 798d7c5a..0b7479d2 100644
--- a/src/anyio/_backends/_asyncio.py
+++ b/src/anyio/_backends/_asyncio.py
@@ -408,9 +408,8 @@ def __init__(self, deadline: float = math.inf, shield: bool = False):
         self._cancel_handle: asyncio.Handle | None = None
         self._tasks: set[asyncio.Task] = set()
         self._host_task: asyncio.Task | None = None
-        self._pending_uncancellations: int | None
         if sys.version_info >= (3, 11):
-            self._pending_uncancellations = 0
+            self._pending_uncancellations: int | None = 0
         else:
             self._pending_uncancellations = None