--- type: reference, concepts --- # Instance-level merge request approval rules **(PREMIUM ONLY)** > Introduced in [GitLab Premium](https://gitlab.com/gitlab-org/gitlab/issues/39060) 12.8. Merge request approvals rules prevent users overriding certain settings on a project level. When configured, only administrators can change these settings on a project level if they are enabled at an instance level. To enable merge request approval rules for an instance: 1. Navigate to **{admin}** **Admin Area >** **{push-rules}** **Push Rules** and expand **Merge requests approvals**. 1. Set the required rule. 1. Click **Save changes**. GitLab administrators can later override these settings in a project’s settings. ## Available rules Merge request approval rules that can be set at an instance level are: - **Prevent approval of merge requests by merge request author**. Prevents non-admins from allowing merge request authors to merge their own merge requests in individual projects. - **Prevent approval of merge requests by merge request committers**. Prevents non-admins from allowing merge request committers to merge merge requests they were committing to in individual projects. - **Prevent users from modifying merge request approvers list**. Prevents non-admins from modifying approvers list in project settings and in individual merge requests.