diff --git a/narwhals/_arrow/dataframe.py b/narwhals/_arrow/dataframe.py
index 6b87f1d8d..a4365e085 100644
--- a/narwhals/_arrow/dataframe.py
+++ b/narwhals/_arrow/dataframe.py
@@ -172,7 +172,7 @@ def __getitem__(
         ),
     ) -> ArrowSeries | ArrowDataFrame:
         if isinstance(item, tuple):
-            item = tuple(list(i) if is_sequence_but_not_str(i) else i for i in item)
+            item = tuple(list(i) if is_sequence_but_not_str(i) else i for i in item)  # type: ignore[assignment]
 
         if isinstance(item, str):
             from narwhals._arrow.series import ArrowSeries
diff --git a/narwhals/_pandas_like/dataframe.py b/narwhals/_pandas_like/dataframe.py
index 8380b48db..df5b923f9 100644
--- a/narwhals/_pandas_like/dataframe.py
+++ b/narwhals/_pandas_like/dataframe.py
@@ -153,7 +153,7 @@ def __getitem__(
         ),
     ) -> PandasLikeSeries | PandasLikeDataFrame:
         if isinstance(item, tuple):
-            item = tuple(list(i) if is_sequence_but_not_str(i) else i for i in item)
+            item = tuple(list(i) if is_sequence_but_not_str(i) else i for i in item)  # type: ignore[assignment]
 
         if isinstance(item, str):
             from narwhals._pandas_like.series import PandasLikeSeries