US frustration rises as North Korea turns down timeline to ditch its nuclear weapons
The proposal, revealed by the 'Vox' website, would require Pyongyang to hand over 60 to 70pc of its nuclear warheads within six to eight months, either to the US or a third country.
The concessions the US would offer in exchange - beyond sanctions relief or removing North Korea from the list of state sponsors of terrorism - remain unknown.
According to the website, the plan has been rejected by North Korean negotiators multiple times over the past two months. Their refusal to comply could explain the frustration expressed by US officials in recent days.
In an interview with Fox News, John Bolton, the US national security adviser, accused Pyongyang of failing to live up to the deal signed between President Donald Trump and Kim Jong-un at the Singapore summit in June, which agreed to work towards denuclearisation of the Korean peninsula.
Mr Bolton said Mr Pompeo would be prepared to return to North Korea for talks, but not for more rhetoric. "What we need is performance from North Korea on denuclearisation," he said. "North Korea has not taken the steps we feel are necessary to denuclearise."
Pyongyang is also growing impatient with the US. When Mr Pompeo went to the country for a third time in July, Kim opted to visit a potato farm rather than meet him.
Yesterday, Pyongyang reiterated its own demand for the US to agree to declare a formal end to the 1950-53 Korean War, which ended with an armistice and not a peace treaty.
Declaring an end to the war is the "demand of our time" and will be the "first process" toward a peace and security guarantee, the state-run 'Rodong Sinmun' newspaper said.
South Korea has viewed the diplomatic rapprochement with North Korea this year as a political coup, and is keen to keep progress towards denuclearisation on track.
Seoul said yesterday that officials from the North and South would meet on Monday to plan for a third summit between Kim and Moon Jae-in, the South Korean president.
South Korea's unification ministry did not elaborate on the location of the summit, although Mr Moon had previously agreed to visit Kim in Pyongyang during the autumn.
Some North Korean analysts remain sceptical about recent developments in negotiations, however. Vipin Narang, an associate professor at Massachusetts Institute of Technology, called Mr Pompeo's plan a "delusional non-starter".
Writing on his Twitter account he said: "If this is what Pompeo has asked for, it's no wonder North Korea has called him a 'robber' or 'gangster-like'. And trying to literally take their nukes away distracts from other realistic objectives like caps."
One major hurdle to the proposal is that North Korea has not even disclosed how many nuclear bombs it actually has. US intelligence officials estimate around 65.