U.S. President Donald Trump has weighed in on the prospect of talks with nuclear-armed North Korea, saying Monday that such a move would come "only under the right conditions," a refrain that came just a day after a top official from the North said for the second time that Pyongyang was open to dialogue with Washington.

"They want to talk. And we want to talk also, only under the right conditions. Otherwise, we're not talking," Trump told a meeting of U.S. governors at the White House in Washington.

"We'll see what happens," Trump said. "That's my attitude: We'll see what happens. But something has to be done."