South Korean President Moon Jae-in sounded a note of caution yesterday over the North's offer of denuclearisation talks, saying it was "too early to be optimistic", even as US leader Donald Trump welcomed the development.
President Trump welcomed Pyongyang's breakthrough declaration -- as relayed by Seoul -- that it wanted to talk to the US and would not need nuclear weapons if its security was guaranteed as positive and apparently sincere.
China's foreign ministry praised the "positive outcomes" of the meeting in Pyongyang, urging both sides to "seize the current opportunity" to promote the denuclearisation of the peninsula.
It followed months of tensions, threats and personal insults between him and the North's leader Kim Jong Un, before the Winter Olympics in the South triggered a flurry of diplomacy.
Moon and Kim will sit down for a summit on the southern side of the Demilitarised Zone next month, Seoul said after its envoys returned from a historic trip to Pyongyang.
Kim said the North would halt provocative missile and nuclear tests while talks are under way, it added.
But Moon told party leaders: "We are only at the starting line and it's too early to be optimistic."
"Inter-Korean talks won't be enough to achieve peace," he said, stressing the importance of Seoul maintaining close co-operation with its security guarantor Washington and adding there would be no let-up in sanctions or pressure purely as a result of inter-Korean dialogue.
Despite welcoming the news, Trump signalled the threat of military action remained on the table should talks fail to make headway, and his administration said it would press ahead with potentially provocative joint war games with South Korea.
In another development, the United States formally concluded Tuesday that North Korea murdered Kim Jong Un's half-brother with the banned VX nerve agent, blasting Pyongyang for deploying a chemical weapon in a packed international airport.
The finding triggered another layer of US economic sanctions against Pyongyang, just as South Korea reported that the regime is ready for talks to end a nuclear standoff.
Kim Jong Nam died in February last year, shortly after two women sprayed his face with a liquid as he walked through Kuala Lumpur airport.
The two women, an Indonesian and a Vietnamese national, are currently on trial in Malaysia where they are accused of using a nerve agent to murder Kim Jong Nam, who lived in exile in China and was seen as a potential rival to his younger half-brother.
The statement gave no details or evidence on how the US had come to their conclusion.
Kim Jong Un's older half-brother had once been seen as their father Kim Jong Il's natural heir, and some reports had suggested that China might be grooming him to replace the younger man in the event of a crisis.
Have we been here before?
Decades of Western attempts to persuade Pyongyang to abandon nuclear weapons have failed. The 1994 Agreed Framework offered the North civilian nuclear reactors and other assistance in exchange for denuclearisation. It fell apart after the US accused the isolated state of covertly restarting its weapons programme and aid delays angered Pyongyang, which eventually stormed out. In 2003 the Beijing-led Six Party Talks began, bringing together the US, both Koreas, Russia, Japan and China in a tortuous process. North Korea pledged to give up its nuclear programmes in 2005, but carried out its first atomic blast the following year. It walked out three years later, detonating its second device soon afterwards. Pyongyang has since continued its weapons drive, accelerating it after Kim inherited power in 2011 from his father Kim Jong Il. Last year it carried out its sixth nuclear blast and launched missiles it said were capable of reaching the US mainland.