0821 GMT November 30, 2020
The North's Foreign Minister Ri Son-gwon accused Washington of hypocrisy and seeking regime change, saying that the hopes of 2018 had "faded away into a dark nightmare".
“Even a slim ray of optimism for peace and prosperity on the Korean Peninsula has faded away into a dark nightmare,” the minister said in a statement.
He said the North had decided to bolster its nuclear deterrent "to cope with the US unabated threats of nuclear war".
It was the latest in a series of statements from Pyongyang aimed at both Washington and Seoul.
North Korea sees little use maintaining a personal relationship between its leader, and Trump if Washington sticks to hostile policies, state media KCNA reported on Friday.
In recent days, Pyongyang has criticized the South over defectors launching leaflets criticizing Kim into the North and announced it was cutting all official communication links with Seoul.
Friday's statement contained some of the harshest criticism Pyongyang has sent Washington's way in recent months, and casts doubt over the future of the two sides' long-stalled nuclear talks process.
Meanwhile, the country's chief ally, China, urged Washington to acknowledge Pyongyang's "legitimate concerns", with Foreign Ministry spokeswoman Hua Chunying saying the North had taken denuclearization measures that merited a commensurate US response.
Chunying told reporters during a daily briefing that one reason for the deterioration in bilateral relations since the Singapore summit was because North Korea’s legitimate concerns had not been resolved.
Trump and Kim were all smiles in front of the world's cameras in Singapore as a North Korean leader met a sitting US president for the first time, and afterward Trump proclaimed on Twitter that "There is no longer a Nuclear Threat from North Korea."
But a second meeting in Hanoi last year to put meat on the bones of the North's Singapore pledge to "work toward complete denuclearization of the Korean Peninsula" collapsed over what Pyongyang would be willing to give up in exchange for sanctions relief.
US diplomats insist that they believe Kim promised in Singapore to give up its arsenal, something Pyongyang has taken no steps to do.
North Korea believes it deserves to be rewarded for its moratorium on nuclear and intercontinental ballistic missile tests and the disabling of its atomic test site, along with the return of jailed US citizens and remains of soldiers killed in the Korean War.
The North is under multiple international sanctions over its banned weapons programs.
"Nothing is more hypocritical than an empty promise," Ri said in his statement, carried by KCNA.
Ri said Pyongyang now believed there was no hope for an improvement "simply by maintaining personal relations between our Supreme Leadership and the US President".
He stopped just short of criticizing Trump by name, but referred to comments that "the master of the White House" had "reeled off time and time again as a boast".
"Never again will we provide the US chief executive with another package to be used... without receiving any returns."
Trump and Kim met a third time in June 2019 in the Demilitarized Zone dividing the Korean Peninsula, when Trump stepped onto North Korean soil – a first for any American president.
But the meeting produced little in terms of tangible progress.
Subsequently, the North repeatedly demanded that the US offer it fresh concessions by December 31, but the deadline came and went.
The process leading to the Singapore summit was brokered by the South's President Moon Jae-in, but his office said Friday it had no comment to make on the anniversary.
AFP and Reuters contributed to the story.