German opposition leader Friedrich Merz, tipped to become the next chancellor, said on Thursday he wanted to win back the lost trust of key allies and ensure Berlin is more assertive on the global stage in a speech laying out his foreign policy plans.

The conservative leader wants to impose strict border controls after knife killings in Aschaffenburg this week.

Friedrich Merz, the conservative front-runner in the race for Germany’s chancellorship, called for a radical overhaul of the country’s migration policy including permanent border checks. The comments come after an asylum seeker from Afghanistan was taken into custody over a fatal stabbing of a two-year-old child and a man in a park on Wednesday.