President Donald Trump said on Saturday that "things are going very well with North Korea" and he plans a second summit with leader Kim Jong-un to try to broker a deal that would entice the North to give up its nuclear weapons.
"We've agreed to meet some time, probably the end of February. We've picked a country, but we'll be announcing it in the future. Kim Jong-un is looking very forward to it and so am I," the president said at the White House.
The initial news of a second meeting with the reclusive North Korean leader came after Trump's 90-minute session on Friday in the Oval Office with a North Korean envoy, Kim Yong-chol, who travelled to Washington to discuss denuclearisation talks.
"We have made a lot of progress as far as denuclearisation is concerned and we're talking about a lot of different things," Mr Trump said, adding it has "not been reported, unfortunately, but it will be. Things are going very with North Korea".
In May, North Korea released three American detainees and sent them home with Secretary of State Mike Pompeo after his meeting with the North Korean leader in Pyongyang.
The second summit signals increased efforts by both countries to continue talks. Mr Trump has exchanged letters with the North Korean leader amid little tangible progress on the vague denuclearisation agreement reached at their first meeting last June in Singapore.
UN Secretary General Antonio Guterres said "it's high time" for serious negotiations between the US and North Korea to outline a road map for the denuclearisation of the Korean Peninsula.
The UN chief said New York on Friday that would allow both sides "to know exactly what the next steps will be and to have predictability in the way negotiations take place".
Mr Trump has spoken several times of having a second summit early this year. Vietnam has been considered as a possible summit venue, along with Thailand, Hawaii and Singapore.
Since the Singapore talks, several analysts have published reports detailing continuing North Korean development of nuclear and missile technology.
A planned meeting between Mr Pompeo and the envoy, who is North Korea's former spy chief, in New York last November was abruptly cancelled. US officials said at the time that North Korea had called off the session.
The special US envoy for North Korea negotiations, Steve Biegun, planned to travel to Sweden for more talks over the weekend.
The talks have stalled over North Korea's refusal to provide a detailed accounting of its nuclear and missile facilities that would be used by inspectors to verify any deal to dismantle them.
The North also has demanded that the US end harsh economic penalties and provide security guarantees before it takes any steps beyond its initial suspension of nuclear and missile tests.
Harry Kazianis, a North Korea expert at the Centre for National Interest, said any talks between the two nations were a positive development, but the hard work of negotiating an agreement had only begun.
As a possible first step, Mr Kazianis said, North Korea could agree to close its nuclear centrifuge plant at Yongbyon in exchange for some relief from US sanctions or a peace declaration ending the Korean War.
The three-year war between North and South Korea ended in 1953 with an armistice, not a peace treaty.
South Korea said it expected the second summit between Mr Trump and Mr Kim to be "a turning point in firmly establishing a permanent peace on the Korean Peninsula".
Mr Kim expressed frustration in an annual New Year's address over the lack of progress in negotiations. But on a visit to Beijing last week, he said North Korea would look to a second summit "to achieve results that will be welcomed by the international community", China's official Xinhua News Agency reported.
Mr Kim's latest trip to China, his fourth since last year, came as the North's strongest ally encouraged negotiations with the US while at the same time arguing for an immediate easing of sanctions.
The US and North Korea seemed close to war at points during 2017. The North staged weapons tests that brought it closer to its nuclear goal of one day being able to threaten anywhere on the US mainland. The two sides then turned to insulting each other: Mr Trump called Mr Kim "Little Rocket Man" and North Korea said Trump was a "dotard".