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Secretary of State John Kerry on Monday said President-elect Donald Trump's tendency to insert himself into the political matters of foreign countries is "inappropriate." Kerry spoke specifically about Trump's recent remarks criticizing German Chancellor Angela Merkel's decision to accept a wave of refugees, which Trump called "one very catastrophic mistake" in an interview with German publication Bild.

"I thought frankly it was inappropriate for a president-elect of the United States to be stepping into the politics of other countries in a quite direct manner," Kerry told CNN's Christiane Amanpour. Kerry, for his part, called Merkel's refugee policy "extremely courageous."