North Korea has returned remains believed to be of 55 US troops killed during the Korean War, bringing renewed hope to families who have waited decades for closure.

The return of the remains, brought to a US base in South Korea, is the latest move in the cautious diplomacy between Washington and Pyongyang.

The repatriation was agreed at the June summit between US President Donald Trump and North Korea’s Kim Jong-un. It is hoped more will follow.

«It’s hard to live your life not knowing what happened to your loved one,» the daughter of one missing serviceman said ahead of Friday’s news.

The Singapore summit, where Mr Trump and Mr Kim agreed to work towards the «complete denuclearisation of the Korean Peninsula», has been criticised for a lack of detail on when or how Pyongyang would renounce nuclear weapons. But the return of US remains was one of four points actually listed in that June declaration, and comes on the 65th anniversary of the signing of the armistice that ended the 1950-1953 Korean War.

It is believed that 55 soldiers have been returned this time, but their remains will need to be forensically tested to ensure they are indeed slain US troops — and it’s possible the identification process could take years.

John Zimmerlee, the son of a US serviceman who is among the missing, said there was no guarantee these were the remains of American soldiers. Mr Zimmerlee, the founder of the Korean War Prisoners Of War and Missing In Action Network, said: «Keep in mind that these 55 remains that are coming back, these are people that they [North Korea] suspected were their enemy during the (Korean) war — not necessarily Americans. «They could be British, they could be Australians, Belgians — could be a lot of different people.»

More than 326,000 Americans fought alongside soldiers from South Korea and a UN coalition during the war to support the South against the Communist North.

Thousands of US military personnel from the Korean war remain unaccounted for and most of them — about 5,300 — were lost in what is now North Korea. The missing US soldiers are among around 33,000 coalition troops still unaccounted for.

The remains are believed to be located at:

Prisoner of war camps — many perished during the winter of 1950
The sites of major battles, such as the areas around Unsan and Chongchon in the north-west of the country — said to contain approximately 1,600 dead
Temporary UN military cemeteries — China and North Korea returned about 3,000 dead Americans in an effort called Operation Glory in 1954, but others remain
The demilitarised zone that separates North and South Korea — said to contain 1,000 bodies

Between 1990 and 2005, 229 sets were returned, but this halted as relations deteriorated with the development of North Korea’s nuclear ambitions.