diff --git a/.github/actions/build_cmake/action.yml b/.github/actions/build_cmake/action.yml
index fa20974af5..6484d0efeb 100644
--- a/.github/actions/build_cmake/action.yml
+++ b/.github/actions/build_cmake/action.yml
@@ -24,6 +24,14 @@ runs:
       with:
         python-version: '3.11'
         miniconda-version: latest
+    - name: Remove defaults channel
+      shell: bash
+      run: |
+        # initialize Conda
+        conda config --show channels
+        conda config --add channels conda-forge
+        conda config --add channels nodefaults
+        conda config --show channels
     - name: Configure build environment
       shell: bash
       run: |
diff --git a/.github/actions/build_conda/action.yml b/.github/actions/build_conda/action.yml
index ff860007b2..5e27872b1c 100644
--- a/.github/actions/build_conda/action.yml
+++ b/.github/actions/build_conda/action.yml
@@ -26,6 +26,14 @@ runs:
         else
           echo "shell=pwsh" >> "$GITHUB_OUTPUT"
         fi
+    - name: Remove defaults channel
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      run: |
+        # initialize Conda
+        conda config --show channels
+        conda config --add channels conda-forge
+        conda config --add channels nodefaults
+        conda config --show channels
     - name: Setup miniconda
       uses: conda-incubator/setup-miniconda@v3
       with: