diff --git a/.github/workflows/cos_integration.yaml b/.github/workflows/cos_integration.yaml
index bca3baac..81c639bc 100644
--- a/.github/workflows/cos_integration.yaml
+++ b/.github/workflows/cos_integration.yaml
@@ -1,59 +1,72 @@
-name: Integration tests with COS
+name: COS Integration tests
 
 on:
   workflow_call:
   workflow_dispatch:
+  pull_request:
+    types: [opened, synchronize, reopened]
+    branches: [main]
+    paths-ignore:
+      - "**.md"
+      - "**.rst"
 
 jobs:
-  integration-tests-with-cos:
-    runs-on: ubuntu-latest
+  integration:
+    runs-on: ubuntu-22.04
     timeout-minutes: 120
     steps:
       - name: Checkout
         uses: actions/checkout@v3
+
       - name: Get IP address of the host
         run: |
           # Finding preferred source ip address by trying to reach destination 2.2.2.2
           # This ip address will be used while enabling metallb
           echo "IPADDR=$(ip -4 -j route get 2.2.2.2 | jq -r '.[] | .prefsrc')" >> $GITHUB_ENV
+
       - name: Setup lxd controller
         uses: charmed-kubernetes/actions-operator@main
         with:
           # The juju version can be any stable version, as long as it is the same as libjuju version used.
-          # Currently, 3.1 is used to keep the version consistent with functional tests (func31)
-          # If, for example, 3.5/stable is used here in the future, the `update python-libjuju dependancy..`
-          # step below should also specify `...3.5.x/g'..` so it updates requirements.txt with the correct version.
-          juju-channel: 3.1/stable
+          # If you update it here, update it also in tests/integration/requirements.txt and 'Setup k8s controller' step below
+          juju-channel: 3.5/stable
           provider: lxd
+
       - name: Save lxd controller name
         id: lxd-controller
         # The `CONTROLLER_NAME` envvar is set by the actions-operator action
         run: echo "name=$CONTROLLER_NAME" >> $GITHUB_OUTPUT
+
       - name: Setup k8s controller
         uses: charmed-kubernetes/actions-operator@main
         with:
-          juju-channel: 3.1/stable
+          # The juju version can be any stable version, as long as it is the same as libjuju version used.
+          # If you update it here, update it also in tests/integration/requirements.txt and 'Setup lxd controller' step above
+          juju-channel: 3.5/stable
           provider: microk8s
           channel: 1.28-strict/stable
           microk8s-addons: "hostpath-storage dns metallb:${{ env.IPADDR }}-${{ env.IPADDR }}"
+
       - name: Save k8s controller name
         id: k8s-controller
         # The `CONTROLLER_NAME` envvar is set by the actions-operator action
         run: echo "name=$CONTROLLER_NAME" >> $GITHUB_OUTPUT
+
       - name: Fix microk8s permissions
-        run: |
-          chmod -R ugo+rwX ~/.kube
-      - name: Update python-libjuju dependency to match juju
-        # The juju CLI version and libjuju version(specified in requirements.txt) should be compatible.
-        # This replaces the libjuju version in requirements.txt and
-        # makes sure the same version is used, even if it has a different/incompatible version.
-        run: sed -E -i 's/^\s*juju\s*~=.+/    juju~=3.1.0/g' tests/integration/requirements.txt
+        run: chmod -R ugo+rwX ~/.kube
+
       - name: Run integration tests
-        run: make integration
+        run: tox -e integration
         env:
           K8S_CONTROLLER: ${{ steps.k8s-controller.outputs.name }}
           LXD_CONTROLLER: ${{ steps.lxd-controller.outputs.name }}
+
       - name: Dump debug log
         if: failure()
-        run: for ctl in $(juju controllers --format json | jq -r '.controllers | keys[]'); do for mdl in $(juju models --format json | jq -r '.models[].name' | grep -v "admin/controller"); do juju debug-log -m $ctl:$mdl --replay --ms --no-tail; done; done || true
+        run: |
+          for ctl in $(juju controllers --format json | jq -r '.controllers | keys[]'); do
+            for mdl in $(juju models --format json | jq -r '.models[].name' | grep -v "admin/controller"); do
+              juju debug-log -m $ctl:$mdl --replay --ms --no-tail
+            done
+          done || true
         shell: bash
diff --git a/tests/integration/requirements.txt b/tests/integration/requirements.txt
index 67679715..caaa3d30 100644
--- a/tests/integration/requirements.txt
+++ b/tests/integration/requirements.txt
@@ -1,7 +1,7 @@
 jinja2
-juju~=3.1.0  # must be compatible with the juju CLI version installed by CI
+juju~=3.5.0  # must be compatible with the juju CLI version installed by CI - see .github/workflows/cos_integration.yaml
 pytest
 pytest-operator
 prometheus-client
 pyinstaller # required to bundle export_mock_metrics script to send it to hw-oberver unit
-tenacity
\ No newline at end of file
+tenacity