One of Britain's best mountaineers who was trapped by armed rebels while on a climbing expedition in Nepal has been speaking of his ordeal.

Stevie Haston, 45, and his wife, Laurence Gouault Haston, were in a party of mountaineers who climbed the 6,750-metre (22,000ft) Ramtang Chang peak in the Himalayas near the border with Tibet.

The exact sequence of events is unclear, but it appears that a number of the group were stopped on the way up to the mountain by suspected Maoist rebels demanding $4,000 (�2,567) in cash.

They were locked up and warned they would be killed if they attempted to summon police or soldiers.

Mr Haston and his wife are still waiting at a higher altitude for the all-clear so they can pass through the narrow valley where the confrontation took place in safety and head for the capital, Kathmandu.

Stevie Haston is an expert rock and ice climber

The mountaineer, an expert rock and ice climber, told BBC Radio Five Live nine of his party were threatened by Maoists on the way up.

"They were locked up and they were asked for money and then they were allowed to go up [the mountain] on the proviso when they came down they paid $4,000.

"Now we are in the situation where we don't really want to go down the valley because we don't want to meet these chaps with guns.

"The lads were locked in, all the shutters were locked and they were threatened and said any attempts to bring the army or police in to help would result in death. He was clear."

British Foreign Office officials say they believe the rest of the party is now safe.

And a spokesman of the Wilderness Express, which handled the climbing expedition, said that arrangements have been made to ensure the safe return of all the climbers.

Ang Phurba Sherpa told the BBC that nine climbers are expected to be back in Kathmandu on Wednesday after an overnight stay in the nearby Taplejung district.

Cash demands from Maoist rebels have become common in some parts of the mountainous country.

Expert mountaineer

John Chick, British Consul in Kathmandu, said: "These Maoist groups have demanded cash before but they have never harmed any climbers."

Mr Haston, originally from London but now living in France, is one of the UK's best known and highly regarded mountaineers and has even descended one Himalayan peak on a snowboard.

He said the Nepal Government had told them there were no rebels in the area.

Team leader, Slovenian Gregor Kreshal, said that he believed the armed men were Maoist rebels.

The rebels have denied involvement in looting tourists and trekkers in the past.