Leading allies of German Chancellor Angela Merkel warned on Thursday that populists would pose a problem for Europe unless mainstream politicians came up with answers after Donald Trump's victory in the U.S. presidential election.

Trump's win has encouraged right-wing parties in Austria, France and the Netherlands, among others. A Politbarometer poll for broadcaster ZDF showed 82 percent of Germans viewed it as bad or very bad, and 65 percent expected relations with the United States to deteriorate under Trump's presidency.

"Demagogic populism is not only a problem in America," Finance Minister Wolfgang Schaeuble told Bild daily. "Elsewhere in the West, too, the political debate is in an alarming state."