diff --git a/tests/widgets/test_widget_open_file.py b/tests/widgets/test_widget_open_file.py
index 7a7cb5e9..60533315 100644
--- a/tests/widgets/test_widget_open_file.py
+++ b/tests/widgets/test_widget_open_file.py
@@ -1,11 +1,17 @@
+import os
+
 import napari
 import numpy as np
+import pytest
 
 from plantseg.io.h5 import create_h5
 from plantseg.io.voxelsize import VoxelSize
 from plantseg.viewer_napari.widgets.io import PathMode, widget_open_file
 
+IN_GITHUB_ACTIONS = os.getenv("GITHUB_ACTIONS") == "true"  # set to true in GitHub Actions by default to skip CUDA tests
+
 
+@pytest.mark.skipif(IN_GITHUB_ACTIONS, reason="GUI tests hangs in GitHub Actions.")
 def test_widget_open_file(make_napari_viewer_proxy, path_h5):
     print("test_widget_open_file called")
     viewer = make_napari_viewer_proxy()
diff --git a/tests/widgets/test_widget_preprocessing.py b/tests/widgets/test_widget_preprocessing.py
index 6b1f8411..0173563e 100644
--- a/tests/widgets/test_widget_preprocessing.py
+++ b/tests/widgets/test_widget_preprocessing.py
@@ -1,3 +1,5 @@
+import os
+
 import napari
 import numpy as np
 import pytest
@@ -8,6 +10,8 @@
 from plantseg.io.voxelsize import VoxelSize
 from plantseg.viewer_napari.widgets.dataprocessing import RescaleModes, widget_rescaling
 
+IN_GITHUB_ACTIONS = os.getenv("GITHUB_ACTIONS") == "true"  # set to true in GitHub Actions by default to skip CUDA tests
+
 
 def create_layer_name(name: str, suffix: str):
     return f"{name}_{suffix}"
@@ -47,6 +51,7 @@ def widget_add_image(image: PlantSegImage) -> LayerDataTuple:
     return image.to_napari_layer_tuple()
 
 
+@pytest.mark.skipif(IN_GITHUB_ACTIONS, reason="GUI tests hangs in GitHub Actions.")
 class TestWidgetRescaling:
     def test_rescaling_from_factor(self, make_napari_viewer_proxy, sample_image):
         viewer = make_napari_viewer_proxy()