Former German Chancellor Angela Merkel criticized Friedrich Merz, her successor as leader of the country’s conservatives, on Thursday for pushing through a bill on tighter immigration control with the help of the far right.

Former German Chancellor Angela Merkel has issued rare public criticism of her successor as the country’s center-right leader, the front-runner in Germany’s election next month, for putting to parliament proposals for tough new migration rules that only passed with the help of a far-right party.

Friedrich Merz, the front-runner to become Germany’s next chancellor, relied on votes from the far-right AfD to push an anti-migration motion through parliament.