Prevent Edit permission to Approvers in Workflow

Hi,

I know this requirement might sound ironical but still would like to know if there is a way to implement this. I understand that Approvers will automatically have Edit access on the item they approve(Because after approval the status will be modified, so the Edit permission is explicitly given to approvers). But I want to chop off this edit access from the approvers and have something like a Read only approver. Which means the approver at no point of time will have edit access on the item he approves. Can this be accomplished?

Thanks,

Vimal