The US is open to negotiations with North Korea aimed at removing nuclear weapons from the region, Secretary of State Rex Tillerson has said.
But he said the US would use military force if necessary.
The foreign minister of China, North Korea’s greatest ally, said a peaceful settlement was the “only right choice”.
Mr Tillerson told a UN Security Council meeting that the threat of North Korea launching a nuclear attack on its neighbours was “real”.
Thousands of US soldiers are stationed in North Korea’s regional neighbours, South Korea and Japan.
He called on other countries to isolate Pyongyang diplomatically.
‘The right agenda’
Asked on Friday by US broadcaster NPR if the US was prepared to hold direct talks with North Korea, Mr Tillerson replied: “Obviously, that would be the way we would like to solve this.
“But North Korea has to decide they’re ready to talk to us about the right agenda.”
He called on UN member states to implement sanctions on North Korea or downgrade diplomatic relations with the country.
Speaking to the UN Security Council, he said the US would use diplomatic and financial measures against North Korea – including potential sanctions on companies or individuals with ties to North Korea – but would be willing to consider military action if necessary.
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For years, he said, North Korea had dictated the terms of its dangerous course of action.
“It’s time for us to retake control of the situation,” he said. “The threat of a North Korean nuclear attack on Seoul or Tokyo is real, and it is likely only a matter of time before North Korea develops the capability to strike the US mainland.”
Chinese Foreign Minister Wang Yi warned against military intervention.
“The use of force does not solve differences and will only lead to bigger disasters,” he said.
“Peaceful settlement of the nuclear issue on the Korean peninsula through dialogue and negotiations represents the only right choice that is practical and viable,” he added.
He also repeated a Chinese offer to halt Pyongyang’s military programme in return for a freeze on joint US-South Korea military drills.
‘Reckless muscle-flexing’
The US has rejected the idea in the past, saying the nuclear programme must be halted first.
Russia said use of force would be “completely unacceptable”. Deputy Foreign Minister Gennady Gatilov also called on North Korea to end its nuclear and missile programmes.
“The combative rhetoric coupled with reckless muscle-flexing has led to a situation where the whole world seriously is now wondering whether there’s going to be a war or not,” he told the Security Council.
“One ill-thought-out or misinterpreted step could lead to the most frightening and lamentable consequences.”
UK Foreign Secretary Boris Johnson told the council that while negotiations “must at some point form part of the solution”, North Korea should first “make verifiable progress towards meeting its obligations to denuclearise the Korean peninsula”.
North Korea has made repeated attempts to miniaturise nuclear warheads and fit them on long-range missiles capable of reaching the US.
It has also made several military shows of strength in recent weeks and the US has sent warships and an anti-missile system to the region in response.
Earlier on Friday, in a wide-ranging interview with Reuters, US President Donald Trump said he feared a “major, major conflict” if negotiation attempts did not work.
Developments that have raised tensions in recent weeks include:
- North Korea executed a failed missile launch and held a massive military parade in an apparent show of strength
- The US deployed a group of warships and a submarine to the region
- Pyongyang reacted angrily, threatening a “super-mighty pre-emptive strike”
- The US began installing a controversial $1bn (£775m) anti-missile system system called Thaad in South Korea – which Mr Trump said South Korea should pay for. Seoul said on Friday there was “no change” in its position that the US pays for it
- Mr Tillerson and US Vice President Mike Pence visited South Korea, reiterating that “all options are on the table” in dealing with the North
Source:BBC