The US and its allies are "making a lot of progress" in dealing with the threat posed by nuclear-armed North Korea, US President Donald Trump said Tuesday while visiting Seoul.

"North Korea is a worldwide threat that requires a worldwide action," he said at a press conference with South Korean President Moon Jae-In, adding the US was prepared to use the full range of its military capabilities if necessary.

But he added: "It makes sense for North Korea to come to the table to make a deal that is good for the people of North Korea and the people of the world."

"I think we are making a lot of progress