Germany's conservative leader Friedrich Merz said on Thursday the U.S. was at risk of sliding into longer-term authoritarian instability, casting doubt on Washington's presence for Germany’s 70th NATO membership anniversary in May.

Friedrich Merz, who is poised to become Germany's chancellor in a CDU-led government, has extensive experience as a lawyer and working with major corporations.

Friedrich Merz, the 69-year-old veteran German politician with a hardline stance on migration and an expensive aviation hobby, is the favorite to become the country’s next chancellor in the February 23 federal election.