Japan and South Korea yesterday agreed to maintain maximum pressure on Pyongyang, while Chinese President Xi Jinping called for patience amid a sudden breakthrough in the nuclear impasse on the Korean peninsula.
The developments came as the South Korean daily Dong-A Ilbo, citing an insider, reported that North Korean leader Kim Jong Un may seek a peace treaty at a summit meeting with United States President Donald Trump expected by May. Mr Kim may also raise the establishment of diplomatic ties and nuclear disarmament.
Yesterday, South Korean National Security Adviser Chung Eui Yong met Mr Xi in Beijing, while National Intelligence Service chief Suh Hoon met Japanese Foreign Minister Taro Kono in Tokyo.
Both South Korean officials met Mr Trump in Washington last week following their meeting with Mr Kim in Pyongyang, at which he conveyed his abrupt U-turn.
Chinese state media quoted Mr Xi as saying: "All sides must exercise patience and be attentive, and show political wisdom to appropriately face and dispel any problems and interference to resuming the talks process."
In Tokyo, Mr Kono lauded the apparent progress, but sought reaffirmation that Seoul's stance will not be softened until there are tangible results towards disarmament.
Mr Kim's overture last week, coming months after engaging in a fiery war of words with Mr Trump and the North making strides in its ballistic missile and nuclear programmes, set off a flurry of diplomatic activity as officials continue to decipher whether Pyongyang is genuine in its intent.
Japan has been strident in warning the world to be cautious against being hoodwinked by the North into giving concessions, with Pyongyang having failed to live up to its end of the bargain in the past.
Japanese officials said at the weekend that Tokyo is ready to offer more than 300 million yen (S$3.7 million) to help the International Atomic Energy Agency inspect the North's nuclear facilities if Pyongyang agrees to inspections.
Mr Chung will fly to Moscow today, as Mr Suh meets Japanese Prime Minister Shinzo Abe. Later this week, Mr Kono and his South Korean counterpart Kang Kyung Wha will visit Washington to meet US Secretary of State Rex Tillerson.
Pyongyang has kept mum - with Seoul acting as its messenger. The South's Unification Ministry spokesman Baik Tae Hyun said yesterday: "I feel they are approaching this matter with caution, and they need time to organise their stance."
North Korean state media has not reported Mr Kim's request for dialogue with Mr Trump, or an inter-Korea summit with South Korean President Moon Jae In slated for next month. Instead, reports continue to warn the US and Japan against warmongering. Mr Baik said the two Koreas have not officially spoken since the South's delegation returned last week.