diff --git a/litellm/llms/vertex_ai.py b/litellm/llms/vertex_ai.py
index 11a1e0c6e..1ee9f434a 100644
--- a/litellm/llms/vertex_ai.py
+++ b/litellm/llms/vertex_ai.py
@@ -95,7 +95,7 @@ def completion(
         mode = "" 
 
         request_str = ""
-        if model in litellm.vertex_chat_models:
+        if model in litellm.vertex_chat_models or ("chat" in model): # to catch chat-bison@003 or chat-bison@004 when google will release it
             chat_model = ChatModel.from_pretrained(model)
             mode = "chat"
             request_str += f"chat_model = ChatModel.from_pretrained({model})\n"
diff --git a/litellm/main.py b/litellm/main.py
index bf35d2a27..6204f0b60 100644
--- a/litellm/main.py
+++ b/litellm/main.py
@@ -1136,7 +1136,7 @@ def completion(
                 )
                 return response
             response = model_response
-        elif model in litellm.vertex_chat_models or model in litellm.vertex_code_chat_models or model in litellm.vertex_text_models or model in litellm.vertex_code_text_models:
+        elif model in litellm.vertex_chat_models or model in litellm.vertex_code_chat_models or model in litellm.vertex_text_models or model in litellm.vertex_code_text_models or custom_llm_provider == "vertex_ai":
             vertex_ai_project = (litellm.vertex_project 
                                  or get_secret("VERTEXAI_PROJECT"))
             vertex_ai_location = (litellm.vertex_location