diff --git a/litellm/files/main.py b/litellm/files/main.py
index 65802be683f..669d50dde41 100644
--- a/litellm/files/main.py
+++ b/litellm/files/main.py
@@ -1016,6 +1016,7 @@ def file_content(
                 vertex_location=vertex_ai_location,
                 timeout=timeout,
                 max_retries=optional_params.max_retries,
+                litellm_params=litellm_params_dict,
             )
         elif custom_llm_provider == "bedrock":
             response = bedrock_files_instance.file_content(
diff --git a/litellm/litellm_core_utils/initialize_dynamic_callback_params.py b/litellm/litellm_core_utils/initialize_dynamic_callback_params.py
index f7e3470bab2..a89dae52316 100644
--- a/litellm/litellm_core_utils/initialize_dynamic_callback_params.py
+++ b/litellm/litellm_core_utils/initialize_dynamic_callback_params.py
@@ -37,8 +37,6 @@ _supported_callback_params = [
     "langfuse_secret_key",
     "langfuse_host",
     "langfuse_prompt_version",
-    "gcs_bucket_name",
-    "gcs_path_service_account",
     "langsmith_api_key",
     "langsmith_project",
     "langsmith_base_url",
@@ -69,7 +67,7 @@ def initialize_standard_callback_dynamic_params(
     """
     Initialize the standard callback dynamic params from the kwargs
 
-    checks if langfuse_secret_key, gcs_bucket_name in kwargs and sets the corresponding attributes in StandardCallbackDynamicParams
+    checks supported request callback params in kwargs and sets the corresponding attributes in StandardCallbackDynamicParams
     """
 
     standard_callback_dynamic_params = StandardCallbackDynamicParams()
diff --git a/litellm/llms/vertex_ai/files/handler.py b/litellm/llms/vertex_ai/files/handler.py
index 48683ba41ae..1a92d521065 100644
--- a/litellm/llms/vertex_ai/files/handler.py
+++ b/litellm/llms/vertex_ai/files/handler.py
@@ -11,6 +11,7 @@ from litellm.integrations.gcs_bucket.gcs_bucket_base import (
 )
 from litellm.litellm_core_utils.cloud_storage_security import (
     VERTEX_AI_MANAGED_GCS_PREFIX,
+    should_allow_legacy_cloud_file_ids,
     validate_managed_cloud_file_id,
 )
 from litellm.llms.custom_httpx.http_handler import get_async_httpx_client
@@ -117,7 +118,10 @@ class VertexAIFilesHandler(GCSBucketBase):
             )
 
     def _extract_bucket_and_object_from_file_id(
-        self, file_id: str, configured_bucket_name: str
+        self,
+        file_id: str,
+        configured_bucket_name: str,
+        litellm_params: Optional[dict] = None,
     ) -> Tuple[str, str]:
         """
         Validate and extract bucket name and object path from file_id.
@@ -134,6 +138,9 @@ class VertexAIFilesHandler(GCSBucketBase):
             scheme="gs://",
             configured_bucket_name=configured_bucket_name,
             allowed_object_prefixes=(VERTEX_AI_MANAGED_GCS_PREFIX,),
+            allow_legacy_cloud_file_ids=should_allow_legacy_cloud_file_ids(
+                litellm_params
+            ),
         )
 
     async def afile_content(
@@ -144,6 +151,7 @@ class VertexAIFilesHandler(GCSBucketBase):
         vertex_location: Optional[str],
         timeout: Union[float, httpx.Timeout],
         max_retries: Optional[int],
+        litellm_params: Optional[dict] = None,
     ) -> HttpxBinaryResponseContent:
         """
         Download file content from GCS bucket for VertexAI files.
@@ -169,6 +177,7 @@ class VertexAIFilesHandler(GCSBucketBase):
         bucket_name, object_path = self._extract_bucket_and_object_from_file_id(
             file_id=file_id,
             configured_bucket_name=gcs_logging_config["bucket_name"],
+            litellm_params=litellm_params,
         )
 
         download_kwargs = {
@@ -205,6 +214,7 @@ class VertexAIFilesHandler(GCSBucketBase):
         vertex_location: Optional[str],
         timeout: Union[float, httpx.Timeout],
         max_retries: Optional[int],
+        litellm_params: Optional[dict] = None,
     ) -> Union[
         HttpxBinaryResponseContent, Coroutine[Any, Any, HttpxBinaryResponseContent]
     ]:
@@ -233,6 +243,7 @@ class VertexAIFilesHandler(GCSBucketBase):
                 vertex_location=vertex_location,
                 timeout=timeout,
                 max_retries=max_retries,
+                litellm_params=litellm_params,
             )
         else:
             return asyncio.run(
@@ -243,5 +254,6 @@ class VertexAIFilesHandler(GCSBucketBase):
                     vertex_location=vertex_location,
                     timeout=timeout,
                     max_retries=max_retries,
+                    litellm_params=litellm_params,
                 )
             )
diff --git a/tests/test_litellm/llms/vertex_ai/files/test_vertex_ai_files_handler.py b/tests/test_litellm/llms/vertex_ai/files/test_vertex_ai_files_handler.py
index 2b71e6c18dc..453a0c14bf9 100644
--- a/tests/test_litellm/llms/vertex_ai/files/test_vertex_ai_files_handler.py
+++ b/tests/test_litellm/llms/vertex_ai/files/test_vertex_ai_files_handler.py
@@ -3,6 +3,7 @@ Test Vertex AI files handler functionality
 """
 
 import asyncio
+from types import MappingProxyType
 import pytest
 from unittest.mock import AsyncMock, patch
 
@@ -66,6 +67,21 @@ class TestVertexAIFilesHandler:
                 configured_bucket_name="test-bucket",
             )
 
+    def test_extract_bucket_and_object_from_file_id_allows_trusted_legacy_flag(self):
+        file_id = "gs%3A%2F%2Ftest-bucket%2Ftest-file.txt"
+        trusted_credentials = MappingProxyType({"allow_legacy_cloud_file_ids": True})
+
+        bucket_name, object_path = self.handler._extract_bucket_and_object_from_file_id(
+            file_id=file_id,
+            configured_bucket_name="test-bucket",
+            litellm_params={
+                "_litellm_internal_model_credentials": trusted_credentials,
+            },
+        )
+
+        assert bucket_name == "test-bucket"
+        assert object_path == "test-file.txt"
+
     def test_extract_bucket_and_object_from_file_id_rejects_no_gs_prefix(self):
         """Test extraction when gs:// prefix is missing"""
         file_id = "test-bucket%2Flitellm-vertex-files%2Ftest-file.txt"