diff --git a/src/keycloak/keycloak_openid.py b/src/keycloak/keycloak_openid.py
index e080e8a..665d21c 100644
--- a/src/keycloak/keycloak_openid.py
+++ b/src/keycloak/keycloak_openid.py
@@ -28,7 +28,7 @@ class to handle authentication and token manipulation.
 """
 
 import json
-from typing import Optional
+from typing import Optional, Union
 
 from jwcrypto import jwk, jwt
 
@@ -582,9 +582,13 @@ class KeycloakOpenID:
         return raise_error_from_response(data_raw, KeycloakPostError)
 
     @staticmethod
-    def _verify_token(token, key, **kwargs):
+    def _verify_token(token, key: Union[str, jwk.JWK, jwk.JWKSet, None], **kwargs):
         # keep the function free of IO
         # this way it can be used by `decode_token` and `a_decode_token`
+        if isinstance(key, str):
+            key = "-----BEGIN PUBLIC KEY-----\n" + key + "\n-----END PUBLIC KEY-----"
+            key = jwk.JWK.from_pem(key.encode("utf-8"))
+
         if key is not None:
             leeway = kwargs.pop("leeway", 60)
             full_jwt = jwt.JWT(jwt=token, **kwargs)
@@ -596,11 +600,6 @@ class KeycloakOpenID:
             full_jwt.token.objects["valid"] = True
             return json.loads(full_jwt.token.payload.decode("utf-8"))
 
-    @staticmethod
-    def _public_key_to_jwk(key: str) -> jwk.JWK:
-        key = "-----BEGIN PUBLIC KEY-----\n" + key + "\n-----END PUBLIC KEY-----"
-        return jwk.JWK.from_pem(key.encode("utf-8"))
-
     def decode_token(self, token, validate: bool = True, **kwargs):
         """Decode user token.
 
@@ -625,7 +624,7 @@ class KeycloakOpenID:
         """
         key = kwargs.pop("key", None)
         if validate and key is None:
-            key = self._public_key_to_jwk(self.public_key())
+            key = self.public_key()
 
         return self._verify_token(token, key, **kwargs)
 
@@ -1261,7 +1260,7 @@ class KeycloakOpenID:
         """
         key = kwargs.pop("key", None)
         if validate and key is None:
-            key = self._public_key_to_jwk(await self.a_public_key())
+            key = await self.a_public_key()
 
         return self._verify_token(token, key, **kwargs)