diff --git a/.github/workflows/python-publish.yml b/.github/workflows/python-publish.yml
index 61735ea5..0f65b5d1 100644
--- a/.github/workflows/python-publish.yml
+++ b/.github/workflows/python-publish.yml
@@ -15,6 +15,8 @@ jobs:
 
   checks:
     uses: ecmwf-actions/reusable-workflows/.github/workflows/qa-pytest-pyproject.yml@v2
+    with:
+      python-version: "3.9"
 
   deploy:
     needs: [checks, quality]