diff --git a/litellm/llms/custom_httpx/llm_http_handler.py b/litellm/llms/custom_httpx/llm_http_handler.py
index fbf16418702..9c1a56b65db 100644
--- a/litellm/llms/custom_httpx/llm_http_handler.py
+++ b/litellm/llms/custom_httpx/llm_http_handler.py
@@ -525,7 +525,7 @@ class BaseLLMHTTPHandler:
         if extra_body is not None:
             data = {**data, **extra_body}
 
-        signing_params: Final[dict[str, object]] = {
+        signing_params: Final[dict[str, object]] = {  # mutable-ok: signer needs a fresh dict
             **litellm_params,
             **optional_params,
         }