Nikki Haley told an emergency meeting of the Security Council in New York City that the US didn’t want war, but that its patience was “not unlimited”.
“Enough is enough,” Haley said. “We have taken an incremental approach, and despite the best of intentions, it has not worked.”
Pyongyang has trialled nuclear weapons on six occasions, but this is the first time it has claimed to have developed a two-stage hydrogen bomb.
Following the US’s calls for the strongest possible sanctions, Russian president Vladimir Putin condemned the nuclear test as “provocative”.
However, he said new sanctions against the regime would be “useless” and “ineffective”, and also warned against creating “global catastrophe” by making military threats.
Yesterday, South Korea’s ambassador to the UN Cho Tae-yul said a resolution had to be “truly biting.”
“Now is the time to take measures that are strong and robust enough to compel North Korea to seriously engage in dialogue,” he said.
“The new resolution must include not only additional measures to further block funds that could possibly flow into North Korea’s illegal nuclear program, but also truly biting and robust measures that Pyongyang finds very painful,” he added.
MOST POPULAR STORIES FROM YAHOO UK:
At least 20 Grenfell survivors have attempted suicide since fire, says charity
One in three Britons eat exactly the same lunch every day
Scotland has been voted the most beautiful country in the world
Jacob Rees-Mogg ‘lined up for ministerial job as May considers’ removing Boris’
On Tuesday, South Korea’s navy carried out live-fire naval drills and warned that if the North provoked them “we will immediately hit back and bury them at sea”.
Following the nuclear test, Theresa May said in a statement: “This latest action by North Korea is reckless and poses an unacceptable further threat to the international community.
“I discussed the serious and grave threat these dangerous and illegal actions present with President Abe in Japan this week and reiterate the call we jointly made for tougher action, including increasing the pace of implementation of existing sanctions and looking urgently in the UN Security Council at new measures.”
Previously, North Korea has tested atomic bombs — similar to those used by the US on Japan in 1945 — but hydrogen, or thermonuclear, bombs can be 1,000 times more powerful.
The bomb was thought to have a power range from 50 kilotonnes to 120 kilotonnes, which would make it at least three times the size of the bomb that destroyed Hiroshima.
It is not yet known if the bomb, which caused a 6.3magnitude earthquake, is a hydrogen bomb, or a less powerful fission-boosted bomb.