How to remove "Widgets" from Theme Options in multisite

Is there a way to remove the link to "widgets" from the themes.php page where on multisite users can change themes? I want users on multisite to be able to switch themes but do not want them to be able to touch the "widgets" sidebar area. I want this to be the same for all blogs (using new blog templates to get this to work) but want to prevent them from editing it. thanks