US Vice-President Mike Pence has said his country and South Korea are in complete agreement on the need to maintain pressure on North Korea.
Speaking on his way home from the Winter Olympics in South Korea, Mr Pence said there was “no daylight” between the two allies on the issue.
The Games has seen better ties between the two Koreas despite tensions over the North’s nuclear programme.
But the US has distanced itself from the North Korean overtures. On Saturday North Korean leader Kim Jong-un invited the South’s President, Moon Jae-in, to Pyongyang for talks.
It would be the first summit in more than a decade between Korean leaders. Mr Moon said the Koreas should “make it happen” and encouraged the North to return to negotiations with the US.