diff --git a/libs/core/tests/unit_tests/messages/test_content_block_factories.py b/libs/core/tests/unit_tests/messages/test_content_block_factories.py
index 51b30f501eb..ab655b2bc20 100644
--- a/libs/core/tests/unit_tests/messages/test_content_block_factories.py
+++ b/libs/core/tests/unit_tests/messages/test_content_block_factories.py
@@ -117,13 +117,6 @@ class TestImageBlockFactory:
         ):
             create_image_block()
 
-    def test_base64_without_mime_type_raises_error(self) -> None:
-        """Test that base64 without mime_type raises ValueError."""
-        with pytest.raises(
-            ValueError, match="mime_type is required when using base64 data"
-        ):
-            create_image_block(base64="iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJ")
-
     def test_with_index(self) -> None:
         """Test image block creation with index."""
         block = create_image_block(url="https://example.com/image.jpg", index=1)
@@ -166,13 +159,6 @@ class TestVideoBlockFactory:
         ):
             create_video_block()
 
-    def test_base64_without_mime_type_raises_error(self) -> None:
-        """Test that base64 without mime_type raises ValueError."""
-        with pytest.raises(
-            ValueError, match="mime_type is required when using base64 data"
-        ):
-            create_video_block(base64="UklGRnoGAABXQVZFZm10IBAAAAABAAEA")
-
 
 class TestAudioBlockFactory:
     """Test create_audio_block factory function."""