diff --git a/dlt/sources/rest_api/__init__.py b/dlt/sources/rest_api/__init__.py
index a634dee0e8..fcc6d6b52f 100644
--- a/dlt/sources/rest_api/__init__.py
+++ b/dlt/sources/rest_api/__init__.py
@@ -411,12 +411,11 @@ def paginate_dependent_resource(
 def _validate_config(config: RESTAPIConfig) -> None:
     c = deepcopy(config)
     _mask_client_config_auth(c.get("client"))
-    resources = c.get("resources")
-    if resources:
-        for resource in resources:
-            if isinstance(resource, str) or isinstance(resource, DltResource):
-                continue
-            _mask_client_config_auth(resource.get("client"))
+    resources = c.get("resources", [])
+    for resource in resources:
+        if isinstance(resource, str) or isinstance(resource, DltResource):
+            continue
+        _mask_client_config_auth(resource.get("client"))
     validate_dict(RESTAPIConfig, c, path=".")