President Donald Trump has warned North Korea to expect "big, big trouble" if anything happens to the US territory of Guam.
Speaking at his Bedminister, New Jersey golf resort, he promised the territory would be "very safe, believe me".
Mr Trump said the US could impose further sanctions, "as strong as they get", on North Korea.
He later spoke to Chinese President Xi Jinping, who stressed the need for a peaceful resolution, Chinese TV said.
President Xi called on "relevant parties" to exercise restraint and avoid words and actions that would exacerbate tension, state TV reported, adding that it was in the interests of both China and the US to pursue the denuclearisation of the Korean peninsula.
"Hopefully, it will all work out," Mr Trump said earlier, striking an upbeat tone after a day of rhetorical brinkmanship.
"Nobody loves a peaceful solution better than President Trump, that I can tell you."
Earlier on Friday, the president said the US military was "locked and loaded" to deal with North Korea, should the need arise.
"Military solutions are now fully in place, locked and loaded, should North Korea act unwisely. Hopefully Kim Jong-un will find another path!" he tweeted.
He spoke as Pyongyang accused him of "driving" the Korean peninsula to the "brink of a nuclear war".