diff --git a/.github/workflows/regression_tests.yml b/.github/workflows/regression_tests.yml
index 6cba07d75..3a57b5533 100644
--- a/.github/workflows/regression_tests.yml
+++ b/.github/workflows/regression_tests.yml
@@ -33,6 +33,17 @@ jobs:
           path: cloudsc
           ref: develop
 
+      - name: Clone ECWAM
+        run: |
+          mkdir ${{ github.workspace }}/ecwam
+          mkdir -p ~/.ssh/ && touch ~/.ssh/known_hosts
+          cat << 'EOF' > ~/.ssh/known_hosts
+          ${{ secrets.BITBUCKET_HOSTKEY }}
+          EOF
+          eval `ssh-agent -s`
+          ssh-add - <<< '${{ secrets.ECWAM_REPOSITORY_SSH_KEY }}'
+          git clone --branch naan-phys-gpu ssh://git@git.ecmwf.int/~nawd/ecwam-bundle.git ${{ github.workspace }}/ecwam
+
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
@@ -55,6 +66,11 @@ jobs:
         run:
           sudo apt-get -o Acquire::Retries=3 install -y libhdf5-dev
 
+      - name: Install ECWAM dependencies
+        run: |
+          sudo apt-get -o Acquire::Retries=3 install -y libopenmpi-dev
+          pip install fypp
+
       - name: Install Loki
         run: |
           ./install --with-claw --with-ofp --with-tests --without-dace
@@ -64,11 +80,19 @@ jobs:
           source loki-activate
           pip install cmake
 
-      - name: Run CLOUDSC regression tests
+      - name: Run CLOUDSC and ECWAM regression tests
         env:
           CLOUDSC_DIR: ${{ github.workspace }}/cloudsc
           CLOUDSC_ARCH: ${{ github.workspace }}/cloudsc/arch/github/ubuntu/gnu/9.4.0
+          ECWAM_DIR: ${{ github.workspace }}/ecwam
+          ECWAM_ARCH: ${{ github.workspace }}/ecwam/arch/github/ubuntu/gnu/9.4.0
           OMP_STACKSIZE: 4G
         run: |
+          mkdir -p ~/.ssh/ && touch ~/.ssh/known_hosts
+          cat << 'EOF' > ~/.ssh/known_hosts
+          ${{ secrets.BITBUCKET_HOSTKEY }}
+          EOF
+          eval `ssh-agent -s`
+          ssh-add - <<< '${{ secrets.ECWAM_REPOSITORY_SSH_KEY }}'
           source loki-activate
-          pytest --cov=transformations/transformations transformations/tests -k cloudsc
+          pytest --cov=transformations/transformations transformations/tests -k 'cloudsc or ecwam'