diff --git a/gigl/common/utils/gcs.py b/gigl/common/utils/gcs.py
index dfb166afa..7f0952ddb 100644
--- a/gigl/common/utils/gcs.py
+++ b/gigl/common/utils/gcs.py
@@ -30,7 +30,7 @@
 def _upload_file_to_gcs(
     source_file_path: LocalUri,
     dest_gcs_path: GcsUri,
-    project: str,
+    project: Optional[str],
     gcs_utils_client: Optional[storage.Client] = None,
 ):
     (
@@ -45,7 +45,9 @@ def _upload_file_to_gcs(
     blob.upload_from_filename(source_file_path.uri)
 
 
-def _pickling_safe_upload_file_to_gcs(obj: Tuple[Tuple[LocalUri, GcsUri], str]):
+def _pickling_safe_upload_file_to_gcs(
+    obj: Tuple[Tuple[LocalUri, GcsUri], Optional[str]],
+):
     file_paths, project = obj
     source_file_path, dest_gcs_path = file_paths
     storage_client = storage.Client(project=project)
@@ -58,7 +60,7 @@ def _pickling_safe_upload_file_to_gcs(obj: Tuple[Tuple[LocalUri, GcsUri], str]):
 
 
 def _upload_files_to_gcs_parallel(
-    project: str, local_file_path_to_gcs_path_map: dict[LocalUri, GcsUri]
+    project: Optional[str], local_file_path_to_gcs_path_map: dict[LocalUri, GcsUri]
 ):
     with ProcessPoolExecutor(max_workers=None) as executor:
         results = executor.map(
@@ -84,6 +86,9 @@ def __init__(self, project: Optional[str] = None) -> None:
             project (Optional[str]): The GCP project ID. Defaults to None.
         """
         self.__storage_client = storage.Client(project=project)
+        # Passing project=None explicitly puts storage.Client in "no project"
+        # mode where client.project is None — a valid, common configuration.
+        self.__project: Optional[str] = self.__storage_client.project
 
     def upload_from_string(self, gcs_path: GcsUri, content: str) -> None:
         bucket_name, blob_name = self.get_bucket_and_blob_path_from_gcs_path(gcs_path)
@@ -133,7 +138,7 @@ def upload_files_to_gcs(
         """
         if parallel:
             _upload_files_to_gcs_parallel(
-                project=self.__storage_client.project,  # ty: ignore[invalid-argument-type]
+                project=self.__project,
                 local_file_path_to_gcs_path_map=local_file_path_to_gcs_path_map,
             )
         else:
@@ -144,7 +149,7 @@ def upload_files_to_gcs(
                 _upload_file_to_gcs(
                     source_file_path=source_file_path,
                     dest_gcs_path=dest_gcs_path,
-                    project=self.__storage_client.project,
+                    project=self.__project,
                     gcs_utils_client=self.__storage_client,
                 )
 
diff --git a/tests/unit/utils/gcs_test.py b/tests/unit/utils/gcs_test.py
index 1a55978d3..e67735887 100644
--- a/tests/unit/utils/gcs_test.py
+++ b/tests/unit/utils/gcs_test.py
@@ -16,6 +16,7 @@ class TestGcsUtils(TestCase):
     def test_upload_from_filelike(self, mock_storage_client):
         # Mock the GCS client, bucket, and blob
         mock_client = MagicMock(spec=Client)
+        mock_client.project = "test-project"
         mock_bucket = MagicMock(spec=Bucket)
         mock_blob = MagicMock(spec=Blob)
 
@@ -40,9 +41,23 @@ def test_upload_from_filelike(self, mock_storage_client):
             filelike, content_type="application/octet-stream"
         )
 
+    def test_init_succeeds_when_client_has_no_project(self):
+        # storage.Client(project=None) with an explicit None is a documented
+        # "no project" mode where client.project is None. GcsUtils must still
+        # be constructible in that mode (it is the default code path, e.g.
+        # FileLoader() with no project).
+        mock_client = MagicMock(spec=Client)
+        mock_client.project = None
+
+        with patch("gigl.common.utils.gcs.storage.Client", return_value=mock_client):
+            gcs_utils = GcsUtils()
+
+        self.assertIsNotNone(gcs_utils)
+
     def test_delete_files_in_bucket_dir(self):
         # Mock the GCS client, bucket, and blob
         mock_client = MagicMock(spec=Client)
+        mock_client.project = "test-project"
         mock_bucket = MagicMock(spec=Bucket)
 
         non_existent_bucket = "test-bucket"