North Korea has released the three Americans detained in the country’s labour camps in a display of goodwill ahead of the looming summit between its Supreme Leader Kim Jong Un and US President Donald Trump, campaigners said.

The three Korean-American detainees — Kim Dong-cheol, Kim Sang-deok and Kim Hak-seong — were released from the labour correction centre in early April and are getting health treatment and ideological education at a hotel near Pyongyang, according to Choi Sung-ryong, the country’s most vocal campaigner for South Korean abductees held in North Korea.

“We heard it through our sources in North Korea late last month. We believe that Mr Trump can take them back on the day of the US-North Korea summit or he can send an envoy to take them back to the US before the summit,” said Mr Choi.

The news came after John Bolton, Mr Trump’s newly appointed national security adviser, told Fox News on Sunday: “If North Korea releases the detained Americans before the North-US summit, it will be an opportunity to demonstrate their authenticity.”

Mike Pompeo, US secretary of state, is believed to have discussed the issue in his secret meeting in Pyongyang with the North Korean dictator over the Easter weekend.

Mr Trump confirmed last week that the US and North Korea had been negotiating for the release of the three Americans.

Among the three detainees, Kim Dong-cheol, a South Korean-born American pastor, was arrested by North Korea in 2015 on charges of spying and sentenced in 2016 to 10 years of hard labour. Kim Hak-seong and Kim Sang-deok, both working for Pyongyang University of Science and Technology, were detained last year on suspicion of “hostile acts”.

North Korean watchers said Pyongyang was paying close attention to the American detainees’ health to ensure no repeat of the case of US university student Otto Warmbier, who died six days after he was released by the North and sent back to the US last June.

“Otto was taken hostage, kept as a prisoner for political purposes, used as a pawn and singled out for exceptionally harsh and brutal treatment by Kim Jong Un,” his father said in a press conference a day before the two Koreas held their historic summit.

At the summit, the two Koreas reaffirmed their push to denuclearise the peninsula and pledged to declare an official end to the 1950-53 Korean war this year.

Moon Chung-in, South Korea’s presidential adviser, said on Monday that it would be difficult to justify the presence of 28,500 US troops in South Korea, if a peace treaty was signed to replace the 1953 armistice.

However, President Moon Jae-in dismissed his adviser’s view a day later. “US troops stationed in South Korea are an issue regarding the alliance between South Korea and the US. It has nothing to do with signing a peace treaty,” his spokesman Kim Eui-keyom quoted the president as saying.

Mr Moon said before the inter-Korean summit that Pyongyang was no longer demanding the removal of US troops from South Korea in return for “complete denuclearisation”. A presidential Blue House official said on Wednesday that Seoul wanted US troops to stay in South Korea to play the role of a mediator in case of military confrontations between neighbouring countries such as China and Japan.

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