A victory for Donald Trump in the U.S. presidential election could affect trans-Atlantic ties, Germany’s foreign minister said Thursday.

Frank-Walter Steinmeier said in an interview that if the Republican candidate wins the presidency it would mean “a lot of uncertainty for the trans-Atlantic relationship.”

Trump’s description of the United States as a country besieged by its enemies was “grotesque,” Steinmeier told the Passauer Neue Presse daily.

He also questioned Trump’s pledges to “make America great again” while keeping the United States out of conflicts around the world.

“I certainly can’t explain how one is supposed to go hand-in-hand with the other,” Steinmeier told the newspaper.

Chancellor Angela Merkel was more diplomatic in her annual summer news conference Thursday.

Asked whether she had experienced any nightmares in which Trump became president, the German leader responded with a “clear no.”

She declined to comment on Trump’s assertion Wednesday that, if elected, he would look into recognizing Russia’s annexation of Crimea.

“I’m not going to meddle in the American domestic election,” said Merkel. “I’m following it with interest, of course, and we’ll await the outcome of the election.”

Germany has strongly opposed the annexation of Crimea.

(AP)