diff --git a/.github/workflows/ci-tests.yml b/.github/workflows/ci-tests.yml
index b0eef1a..8f54e30 100644
--- a/.github/workflows/ci-tests.yml
+++ b/.github/workflows/ci-tests.yml
@@ -49,7 +49,7 @@ jobs:
 
       - name: "Install dependencies"
         run: |
-          conda install --yes numpy pytest pytest-mock iris xarray filelock requests
+          conda install --yes numpy pytest pytest-mock iris xarray filelock requests zarr aiohttp
 
       - name: "Install *latest* Iris"
         run: |