US Secretary of State Rex Tillerson has warned that if North Korea does not choose to negotiate on giving up its nuclear weapons it could trigger a military response.

After a meeting of US allies on how to beef up the campaign of sanctions, Mr Tillerson stressed that the Trump administration seeks a diplomatic resolution in the nuclear standoff, but he said the North has yet to show itself to be a “credible negotiating partner.”

He added US-North Korea talks would require a “sustained cessation” of threatening behaviour.

Mr Tillerson declined to comment on whether the White House is considering limited military action against Pyongyang, in response to reports that some in the Trump administration advocate military action to give the North a “bloody nose”.

“We all need to be very sober and clear-eyed about the current situation,” Mr Tillerson said when he was asked whether Americans should be concerned about the possibility of a war.

He said North Korea has continued to make significant advances in its nuclear weapons through the thermonuclear test and progress in its intercontinental missile systems.

“We have to recognise that the threat is growing and that if North Korea does not choose the pathway of engagement, discussion, negotiation then they themselves will trigger an option,” he said.

Tillerson North Korea
Officials discussed sanctions, preventing the spread of weapons and diplomatic options. (Jonathan Hayward/The Canadian Press/AP)

His uncompromising message came after a gathering in Vancouver of 20 nations that were on America’s side during the Korean War, where there was scepticism among the allies over North Korea’s sincerity in its recent diplomatic opening with the US-allied South.

Despite Washington’s tough stance and determination to keep up the pressure on North Korea, president Donald Trump has signalled openness to talks with the North under the right circumstances.

After months of insults and blood-curdling threats which he has traded with North Korean leader Kim Jong Un, Mr Trump suggested in an interview last week that the two leaders could have a positive relationship.

Mr Tillerson declined to say on Tuesday whether Trump has spoken directly to Kim.

“I don’t think it’s useful to comment” he said.

“We are at a very tenuous stage in terms of how far North Korea has taken their program and what we can do to convince them to take an alternative path. And so when we get into who’s talking to who and what was said, if we want that to be made known or made public we will announce it.”