In Washington this week, the United States special representative for North Korea, Stephen Biegun, said that diplomacy was "still very much alive", though he did not say if there had been any negotiations since the summit, or outline any plans for further talks.
United Nations -led sanctions were a major sticking point, with Pyongyang calling for the lifting of several Security Council sanctions against it in return for dismantling the Yongbyon nuclear complex under the monitoring of US experts. Pyongyang announced that Kim Jong-un will shortly decide whether he intends to continue his moratorium on missile and nuclear tests after the failure of the Hanoi summit to make progress toward resolving the standoff on the Korean peninsula. North Korea expert Joshua Pollack said North Korea may be delivering an ultimatum.
"Personal relations between the two supreme leaders are still good and the chemistry is mysteriously wonderful", she said. "(We) can't assess the current situation only with Vice Foreign Minister Choe's remarks", Cheong Wa Dae said. We closely monitor the situation.
The summit also saw the US reportedly give the North Korean leader a written and expanded American definition of "complete denuclearization".
Choe blamed the USA for the failure, saying that Secretary of State Michael Pompeo and National Security Adviser John Bolton "created the atmosphere of hostility and mistrust" and "obstructed" Kim and Trump´s "constructive effort".
Ms Choe said that North Korea's demand during the recent summit was for five key economic sanctions to be lifted, not all sanctions, as Mr Trump said after talks broke down.
"What is clear is that the US has thrown away a golden opportunity this time". "It is likely to gauge the USA reaction in the days ahead before making a decision to launch a rocket", he said. This week, a US representative for North Korea said the USA administration would not accept a phased denuclearization, but insisted US and North Korean officials are still closely engaged on the subject.
At the summit, US President Donald Trump and Kim ended their meeting sooner than scheduled without reaching any agreement.
U.S. Sen. Ed Markey took issue Friday with reports suggesting that North Korea may suspend diplomatic talks with the United States and resume missile testing unless the Trump administration lifts various sanctions - a threat the Massachusetts Democrat called "nothing short of extortion".
North Korea has not conducted nuclear or missile testing since 2017.
Miller explains those are the sanctions that came after 2016 and have "effectively cut off North Korea, their supplies for coal, copper, crude oil, those are the ones that basically North Korea wanted relief [from]".
The North´s warning came amid concerns over its satellite rocket launch site, where some rebuilding activity has been observed in recent weeks, triggering global alarm that Pyongyang might be preparing a long-range missile or space launch.
Commercial satellite images, released by USA -based think tanks, suggested the North may be rebuilding its Dongchang-ri long-range rocket test site close to the border with China. Recent satellite imagery shows that construction to rebuild the site began between February 20 and March 2. At the launch pad, the rail-mounted transfer/processing structure had been moved to the edge of the pad and the environmental cover had been closed around the gantry tower.
In Beijing, Premier Li Keqiang urged patience and further dialogue between North Korea and the United States.
"[Kim Jong Un] pretended to play the Tongchang-ri card, but never meant to fire a missile to place pressure on the United States", Kim Yong-hyun said.
North Korea acknowledged for the first time last Friday that the Hanoi summit ended "unexpectedly without an agreement".