The South Carolina Republican made his comments about Kim Jong Un on Twitter a day after having dinner with Trump.
Graham tweet: Pres @ realDonaldTrumpis NOT going to let the nutjob in North Korea develop a missile - with a nuclear weapon on top - that can hit the US.
In a Fox News interview earlier Tuesday, Graham said he preferred to curb North Korean aggression through diplomacy, "using China," Pyongyang's only major ally, to stop North Korea from trying to develop intercontinental ballistic missiles. Graham said he sees military force as a "last resort."
"[Trump] doesn't want a war any more than I do, but he's not going to let them get a missile. That's where they're headed. And China needs to up their game to stop this before it gets too late," Graham told Fox.
Graham and Republican Sen. John McCain of Arizona, like Graham a noted foreign policy hawk, both attended the dinner with Trump. Graham's office did not immediately respond to a request to comment on what they specifically discussed. McCain's office declined to comment.