diff --git a/litellm/llms/bedrock/base_aws_llm.py b/litellm/llms/bedrock/base_aws_llm.py
index bbd4988b204..1c7268ffa22 100644
--- a/litellm/llms/bedrock/base_aws_llm.py
+++ b/litellm/llms/bedrock/base_aws_llm.py
@@ -1671,6 +1671,25 @@ class BaseAWSLLM:
         return request_headers_dict, request.body
 
 
+def sign_aws_json_post(
+    get_credentials: Callable[[], Credentials],
+    service_name: str,
+    aws_region_name: str | None,
+    url: str,
+    body: str,
+    headers: Mapping[str, str],
+) -> AWSPreparedRequest:
+    try:
+        from botocore.auth import SigV4Auth
+        from botocore.awsrequest import AWSRequest
+    except ImportError:
+        raise ImportError(f"Missing boto3 to call {service_name}. Run 'pip install boto3'.")
+
+    aws_request: Final = AWSRequest(method="POST", url=url, data=body, headers=headers)
+    SigV4Auth(get_credentials(), service_name, aws_region_name).add_auth(aws_request)
+    return aws_request.prepare()
+
+
 _SignParams = ParamSpec("_SignParams")
 _SignedRequest = TypeVar("_SignedRequest")
 
diff --git a/litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py b/litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py
index 6085bc2bfce..037f663044f 100644
--- a/litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py
+++ b/litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py
@@ -86,9 +86,6 @@ from litellm.utils import ProviderConfigManager
 from .passthrough_endpoint_router import PassthroughEndpointRouter
 
 if TYPE_CHECKING:
-    from botocore.awsrequest import AWSPreparedRequest
-    from botocore.credentials import Credentials
-
     from litellm.proxy.proxy_server import ProxyConfig as _ProxyConfig
     from litellm.router import Router
 
@@ -1134,6 +1131,7 @@ async def bedrock_proxy_route(
     )
 
     # Add or update query parameters
+    from litellm.llms.bedrock.base_aws_llm import sign_aws_json_post
     from litellm.llms.bedrock.chat import BedrockConverseLLM
 
     bedrock_llm: Final = BedrockConverseLLM()
@@ -1143,7 +1141,7 @@ async def bedrock_proxy_route(
     except Exception as e:
         raise HTTPException(status_code=400, detail={"error": e})
     prepped: Final = await asyncio.to_thread(
-        _sign_aws_json_post,
+        sign_aws_json_post,
         get_credentials=bedrock_llm.get_credentials,
         service_name="bedrock",
         aws_region_name=aws_region_name,
@@ -1178,25 +1176,6 @@ async def bedrock_proxy_route(
     return received_value
 
 
-def _sign_aws_json_post(
-    get_credentials: Callable[[], Credentials],
-    service_name: str,
-    aws_region_name: str | None,
-    url: str,
-    body: str,
-    headers: Mapping[str, str],
-) -> AWSPreparedRequest:
-    try:
-        from botocore.auth import SigV4Auth
-        from botocore.awsrequest import AWSRequest
-    except ImportError:
-        raise ImportError(f"Missing boto3 to call {service_name}. Run 'pip install boto3'.")
-
-    aws_request: Final = AWSRequest(method="POST", url=url, data=body, headers=headers)
-    SigV4Auth(get_credentials(), service_name, aws_region_name).add_auth(aws_request)
-    return aws_request.prepare()
-
-
 COMPREHEND_MEDICAL_TARGET_PREFIX: Final = "ComprehendMedical_20181030"
 
 
@@ -1257,11 +1236,11 @@ async def comprehend_medical_proxy_route(
     if "stream" in data:
         raise HTTPException(status_code=400, detail="'stream' is not a Comprehend Medical request member")
 
-    from litellm.llms.bedrock.base_aws_llm import BaseAWSLLM
+    from litellm.llms.bedrock.base_aws_llm import BaseAWSLLM, sign_aws_json_post
 
     target_url: Final = f"https://comprehendmedical.{aws_region_name}.{get_aws_dns_suffix(aws_region_name)}/"
     prepped: Final = await asyncio.to_thread(
-        _sign_aws_json_post,
+        sign_aws_json_post,
         get_credentials=partial(BaseAWSLLM().get_credentials, aws_region_name=aws_region_name),
         service_name="comprehendmedical",
         aws_region_name=aws_region_name,
diff --git a/tests/test_litellm/llms/bedrock/event_loop_probe.py b/tests/test_litellm/llms/bedrock/event_loop_probe.py
index 68acce308b8..c347247ec32 100644
--- a/tests/test_litellm/llms/bedrock/event_loop_probe.py
+++ b/tests/test_litellm/llms/bedrock/event_loop_probe.py
@@ -4,12 +4,14 @@ from __future__ import annotations
 
 import asyncio
 import threading
+import time
 from datetime import datetime, timedelta, timezone
 from typing import Final
 
 from botocore.credentials import RefreshableCredentials
 
 REFRESH_RELEASE_TIMEOUT_SECONDS: Final = 2.0
+REFRESH_START_TIMEOUT_SECONDS: Final = 10.0
 
 
 class EventLoopProbe:
@@ -47,6 +49,9 @@ class EventLoopProbe:
         )
 
     async def release_refresh_from_the_loop(self) -> None:
+        deadline: Final = time.monotonic() + REFRESH_START_TIMEOUT_SECONDS
         while not self.refresh_started.is_set():
+            if time.monotonic() > deadline:
+                raise TimeoutError("signing finished without ever starting a credential refresh")
             await asyncio.sleep(0.005)
         self.loop_served.set()