diff --git a/pydantic_ai_slim/pydantic_ai/models/__init__.py b/pydantic_ai_slim/pydantic_ai/models/__init__.py
index eb82de2bc..9f52feca5 100644
--- a/pydantic_ai_slim/pydantic_ai/models/__init__.py
+++ b/pydantic_ai_slim/pydantic_ai/models/__init__.py
@@ -6,12 +6,15 @@
 
 from __future__ import annotations as _annotations
 
+import asyncio
+import weakref
 from abc import ABC, abstractmethod
-from collections.abc import AsyncIterator, Iterator
+from collections.abc import AsyncIterator, Iterator, MutableMapping
 from contextlib import asynccontextmanager, contextmanager
 from dataclasses import dataclass, field
 from datetime import datetime
 from functools import cache
+from types import TracebackType
 
 import httpx
 from typing_extensions import Literal, TypeAliasType
@@ -506,15 +509,48 @@ def cached_async_http_client(*, provider: str | None = None, timeout: int = 600,
 @cache
 def _cached_async_http_client(provider: str | None, timeout: int = 600, connect: int = 5) -> httpx.AsyncClient:
     return httpx.AsyncClient(
-        transport=_cached_async_http_transport(),
+        transport=_get_transport_for_loop(),
         timeout=httpx.Timeout(timeout=timeout, connect=connect),
         headers={'User-Agent': get_user_agent()},
     )
 
 
 @cache
-def _cached_async_http_transport() -> httpx.AsyncHTTPTransport:
-    return httpx.AsyncHTTPTransport()
+def _get_transport_for_loop() -> _PerLoopTransport:
+    return _PerLoopTransport()
+
+
+class _PerLoopTransport(httpx.AsyncBaseTransport):
+    def __init__(self):
+        self.transports: MutableMapping[asyncio.AbstractEventLoop, httpx.AsyncHTTPTransport] = (
+            weakref.WeakKeyDictionary()
+        )
+
+    def get_transport(self) -> httpx.AsyncHTTPTransport:
+        # Clean the dictionary of closed loops
+        for loop in list(self.transports.keys()):
+            if loop.is_closed():
+                del self.transports[loop]
+
+        return self.transports.setdefault(asyncio.get_running_loop(), httpx.AsyncHTTPTransport())
+
+    async def __aenter__(self):
+        await self.get_transport().__aenter__()
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[BaseException] | None = None,
+        exc_value: BaseException | None = None,
+        traceback: TracebackType | None = None,
+    ) -> None:
+        await self.get_transport().__aexit__(exc_type, exc_value, traceback)
+
+    async def handle_async_request(self, request: httpx.Request) -> httpx.Response:
+        return await self.get_transport().handle_async_request(request)
+
+    async def aclose(self) -> None:
+        await self.get_transport().aclose()
 
 
 @cache