The US has denied claims by North Korea that Donald Trump’s administration is using “gangster-like diplomacy” tactics.

Leader Kim Jong-un issued a statement through state-run Korean Central News Agency which said the talks with Mike Pompeo, US secretary, were also “regrettable”.

North Korean officials accused the US of unreasonable demands on CVID – the “complete, verifiable and irreversible denuclearisation” of the hermit state.

“We had expected that the US side would offer constructive measures that would help build trust based on the spirit of the leaders’ summit ... we were also thinking about providing reciprocal measures. Our expectations and hopes were so naive it could be called foolish,” read the statement from an unnamed foreign ministry spokesperson.

“The US is fatally mistaken if it went to the extent of regarding that [North Korea] would be compelled to accept, out of its patience, demands reflecting its gangster-like mindset,” it added.

“If those requests were gangster-like, the world is a gangster,” Mr Pompeo said after the meetings concluded, noting that the US is not the first country to make such demands of Pyongyang and that the sanctions were agreed to by several members of the United Nations.

“When we spoke to them about denuclearisation, they did not push back,” he added.

Singapore Summit 2018: Donald Trump says North Korea will 'dismantle missile test site'

North Korea, however, thought his tone was “very concerning” because it has led to a “dangerous phase that might rattle our willingness for denuclearisation that had been firm”.

“The road ahead will be difficult and challenging and we know that critics will try to minimise the work that we’ve achieved,” Mr Pompeo said as he was returning to the US.

His take on the talks was wildly different than Pyongyang’s – he called them “productive” and done “in good faith”.

State department spokesperson Heather Nauert tweeted that Mr Pompeo noted negotiators “made progress on almost all the central issues”.

These recent differences in perception have fuelled critics of the agreement signed by the leaders in Singapore, which they said were too vague to guarantee compliance by Kim Jong-un’s regime and did not adequately define what denuclearisation should look like to both sides.

The joint statement simply read: “President Trump committed to provide security guarantees to [North Korea], and Chairman Kim Jong Un reaffirmed his firm and unwavering commitment to the complete denuclearization of the Korean peninsula.”

Mr Trump immediately declared the summit a resounding success and assured Americans they did not have to worry about a nuclear weapons attack anymore.

However, recent intelligence reports have suggested North Korea has not actually stopped developing its nuclear weapons programme. Critics also point out that Mr Trump may have given away any advantage the US had when he declared an end to joint US-South Korea military exercises in the region, reportedly at Kim Jong-un’s request.

Mr Trump used the same language as the North Korean leader when suspending drills, calling them “provocative”. He also said the “war games” were “expensive”.

In May 2018, Pyongyang had said the joint US and South Korean air force drills, which included fighter jets, was a “rehearsal for [an] invasion of the North and a provocation amid warming inter-Korean ties ... [it is an] intentional military provocation running counter to the positive political development on the Korean Peninsula”.

North Korea had cancelled scheduled peace talks with South Korean President Moon Jae-in and threatened not to meet Mr Trump, so the freeze may have been a concession to get North Korea to Singapore in the first place.

North Korea Military Parade Show all 6 1 /6 North Korea Military Parade North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, a military parade is held at Kim Il Sung Square in Pyongyang, Thursday, Feb. 8 2018, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade This screen grab taken from North Korea's KCTV on February 8, 2018 shows members of North Korea's military taking part in a parade, with missiles being displayed, in Kim Il Sung Square in Pyongyang. North Korea staged a military parade in Pyongyang on February 8 to mark the 70th anniversary of its armed forces, in a show of strength just a day before the Pyeongchang 2018 Winter Olympic Games open in the South. / AFP PHOTO / KCTV / KCTV / -----EDITORS NOTE --- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / KCTV" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS - NO ARCHIVESKCTV/AFP/Getty Images AFP/Getty Images North Korea Military Parade In this image made from video released by KRT, North Korean soldiers march during a military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, North Korean leader Kim Jong Un, right, inspects honor guards, along with his wife Ri Sol Ju, center, during a military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, North Korean leader Kim Jong Un, center, watches the military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade This screen grab taken from North Korea's KCTV on February 8, 2018 shows North Korean leader Kim Jong Un speaking during a military parade in Kim Il Sung Square in Pyongyang. North Korea staged a military parade in Pyongyang on February 8 to mark the 70th anniversary of its armed forces, in a show of strength just a day before the Pyeongchang 2018 Winter Olympic Games open in the South. / AFP PHOTO / KCTV / KCTV / -----EDITORS NOTE --- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / KCTV" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS - NO ARCHIVESKCTV/AFP/Getty Images AFP/Getty Images

The idea of pausing military drills in exchange for at least a temporary halt in North Korea’s nuclear weapons development was first put forward by China.

Foreign minister Wang Yi had said in March 2017: “China’s suggestion is, as a first step, for North Korea to suspend nuclear activity, and for the US and South Korea to also suspend large-scale military drills.” Mr Trump has not appeared to appreciate Chinese president Xi Jinping’s meetings with Kim Jong-un, however.

Among the steps taken by Mr Pompeo during his two days in North Korea were the formation of a working group to determine exactly how North Korea’s denuclearisation will be verified and meeting to discuss the return of remains of Americans killed during the Korean War.

He said Pentagon officials would be meeting with North Korean officials on or about 12 July in the demilitarised zone (DMZ) on the border of the two Koreas to discuss repatriation of remains.

Speaking to members of the US-Vietnamese business community in Hanoi following his trip to North Korea, Mr Pompeo said: “In light of the once-unimaginable prosperity and partnership we have with Vietnam today, I have a message for chairman Kim Jong-un: President Trump believes your country can replicate this path.”