diff --git a/descope/auth.py b/descope/auth.py
index 518722627..42a20c5d0 100644
--- a/descope/auth.py
+++ b/descope/auth.py
@@ -33,7 +33,7 @@ class Auth:
 
     def __init__(
         self,
-        project_id: str,
+        project_id: str = None,
         public_key: str = None,
         skip_verify: bool = False,
     ):
@@ -188,6 +188,14 @@ def validate_phone(method: DeliveryMethod, phone: str):
                 400, ERROR_TYPE_INVALID_ARGUMENT, "Invalid delivery method"
             )
 
+    def refresh_token(self, refresh_token: str) -> dict:
+        uri = Auth._compose_refresh_token_url()
+        response = self.do_get(uri, None, None, refresh_token)
+
+        resp = response.json()
+        auth_info = self._generate_auth_info(resp, refresh_token)
+        return auth_info
+
     @staticmethod
     def _validate_and_load_public_key(public_key) -> Tuple[str, jwt.PyJWK, str]:
         if isinstance(public_key, str):
@@ -327,14 +335,6 @@ def _get_default_headers(self, pswd: str = None):
         headers["Authorization"] = f"Basic {base64.b64encode(bytes).decode('ascii')}"
         return headers
 
-    def refresh_token(self, refresh_token: str) -> dict:
-        uri = Auth._compose_refresh_token_url()
-        response = self.do_get(uri, None, None, refresh_token)
-
-        resp = response.json()
-        auth_info = self._generate_auth_info(resp, refresh_token)
-        return auth_info
-
     def _validate_and_load_tokens(self, session_token: str, refresh_token: str) -> dict:
         if not session_token:
             raise AuthException(
diff --git a/descope/descope_client.py b/descope/descope_client.py
index 0291925d2..6c2e612ea 100644
--- a/descope/descope_client.py
+++ b/descope/descope_client.py
@@ -17,7 +17,7 @@ class DescopeClient:
 
     def __init__(
         self,
-        project_id: str,
+        project_id: str = None,
         public_key: str = None,
         skip_verify: bool = False,
     ):
@@ -106,3 +106,6 @@ def logout(self, refresh_token: str) -> requests.Response:
 
         uri = EndpointsV1.logoutPath
         return self._auth.do_get(uri, None, None, refresh_token)
+
+    def refresh_token(self, refresh_token: str) -> dict:
+        return self._auth.refresh_token(refresh_token)
diff --git a/samples/otp_sample_app.py b/samples/otp_sample_app.py
index b9345e705..c82880b36 100644
--- a/samples/otp_sample_app.py
+++ b/samples/otp_sample_app.py
@@ -46,7 +46,7 @@ def main():
 
         try:
             logging.info("refreshing the session token..")
-            claims = descope_client._auth.refresh_token(refresh_token)
+            claims = descope_client.refresh_token(refresh_token)
             logging.info(
                 "going to revalidate the session with the newly refreshed token.."
             )