Peter Reynolds, 79, and partner Barbie, 76, are being kept at the Pul-e-Charkhi maximum-security prison in Kabul, Afghanistan without charge after being arrested in February.

They were detained with their interpreter and American friend, Faye Hall, when they flew to an airstrip close to their home in Bamiyan. They say they were quizzed on their documentation and asked how they had Afghan passports, before they were led away and jailed alongside monsters and murderers, the Mirror reported.

Mr Reynolds told the Sunday Times: "I've been joined up with rapists and murderers by handcuffs and ankle cuffs, including a man who killed his wife and three children, shouting away, a demon-possessed man.

The atmosphere is pretty shocking. The prison guards ... beat people with a piece of piping. It's a horrible atmosphere, the nearest thing to hell I can imagine."

The couple have lived in Afghanistan for 18 years after marrying there in 1970 and returning to set up a business known as Rebuild, which provides training in schools and businesses.

When the Taliban returned to power in 2021 they opted to stay and had not suffered any issues until their sudden arrest.

Although their friend was later released, they remain behind bars with Barbie's jail conditions said to be worse than her husband. Last month their daughter, Sarah Entwistle, said the pair were separated, with Mr Reynolds moved to an "undisclosed location" and his health has "significantly deteriorated".

She said at the time: "We hear he now has a chest infection, a double eye infection and serious digestive issues due to poor nutrition. Without immediate access to necessary medication, his life is in serious danger."

In a statement reported by the BBC in February, Taliban official Abdul Mateen Qani said: "A series of considerations is being taken into account, and after evaluation, we will endeavour to release them as soon as possible."

Mr Qani added the three foreign nationals had Afghan passports and national ID cards.

It was hoped the couple would be released during the recent Eid holiday but they remain locked up. It was previously reported the couple's family did not want the UK Government to get involved with the case.