BEIJING: Countries around the world swiftly condemned North Korea's announcement that it had tested a hydrogen bomb Sunday, with South Korea calling for the "strongest punishment" against Pyongyang while key ally China strongly condemned it.
Tensions on the Korean peninsula have spiralled in recent weeks, with North Korea testing an intercontinental ballistic missile (ICBM) and threatening to fire missiles towards the US Pacific island of Guam and President Donald Trump warning he would rain "fire and fury" on the country.
Last week the North fired a missile over Japan and into the Pacific.
South Korean President Moon Jae-In called for the "strongest punishment" against the North over its nuclear test, including new UN sanctions to "completely isolate" it.
China, which is hosting a summit of the five BRICS nations, said it "expresses resolute opposition and strong condemnation" over Pyongyang's sixth nuclear test, which was felt in Chinese cities hundreds of kilometres from North Korea's borders.
China, a key provider of aid and trade to the North, is seen as the only country holding any real influence over its truculent neighbour. But relations have become more strained in recent years, in part because of Pyongyang's dogged pursuit of its nuclear programme in the face of international condemnation.
The North should "stop taking mistaken actions which worsen the situation and are also not in line with its own interests, and effectively return to the track of solving the problem through dialogue," the Chinese foreign ministry said.
President Xi Jinping and his Russian counterpart Vladimir Putin remained silent on the subject at the opening of the BRICS summit in Xiamen, which includes Brazil, India and South Africa.
'Creating serious threat'
Russia's foreign ministry however expressed "strongest condemnation" of Pyongyang's actions, while adding "it is imperative to remain calm and to refrain from any actions that lead to a further escalation of tension".
The ministry said it regretted that the leadership of North Korea was "creating a serious threat" for the region and warned that "the continuation of such a line is fraught with serious consequences" for Pyongyang.
Japanese Prime Minister Shinzo Abe slammed the test as "absolutely unacceptable" and said North Korea's nuclear and missile programmes now pose a more "grave and urgent" threat to his country.
"Whether we can stop North Korea's reckless actions that threaten world peace depends on the cooperation and solidarity of the international community," he added.
French President Emmanuel Macron also called for a "very firm" response by the international community and urged the UN Security Council to "quickly react".
EU foreign policy chief Federica Mogherini said she was looking forward "to the UN Security Council addressing the matter and taking a firm and effective stand".
NATO secretary general Jens Stoltenberg condemned the test as "yet another flagrant violation" of multiple UN Security Council resolutions.
"NATO is concerned by Pyongyang's destabilising pattern of behaviour, which poses a threat to regional and international security," he said.
Pyongyang, for its part, called the nuclear detonation "a perfect success".
The test was substantially larger than previous ones, generating a 6.3 magnitude earth tremor according to US monitors.
Washington has not responded so far.
After North Korea sent a missile over Japan last week, Trump tweeted that the time for talks was over.
"The US has been talking to North Korea, and paying them extortion money, for 25 years. Talking is not the answer!" he wrote.
Trump had previously pledged the North would not get an ICBM and has warned that Washington's weapons are "locked and loaded".