Prince Harry has paid tribute to a team of injured servicemen whose attempt to climb Mount Everest has been abandoned because of safety concerns.
The five current and former soldiers taking part in the Walking With The Wounded challenge will leave the Himalayas later this week. A charity spokesman said the mountain was "a death trap" and the already difficult task of climbing 8,848m (29,028ft) above sea level to the summit had been made "almost impossible".
Expedition patron Prince Harry, speaking at the Atlantic Council in Washington where he was given a humanitarian award, said: "Last year, I struggled to keep up with the four British soldiers whom I joined for part of their expedition to walk to the North Pole. Each of these men had recently been gravely wounded on the battlefields of Afghanistan. Theirs was the fastest team to reach the Pole that season.
"At this very moment, another team of our wounded are returning from Mount Everest. Sadly, I have to be the first to say they have been frustrated from reaching the summit by the unusually warm weather, which brings particularly dangerous conditions. However, the mere fact that they are up there on that fearsome peak, I find totally amazing."
Russell Brice, expedition leader who has led groups up Everest over the past 25 years, said: "I've never seen conditions like this before - the mountain is in a very critical condition indeed."
The team arrived in Nepal at the end of March and planned to reach the summit of Everest by the end of this month.
Walking With The Wounded co-founder Edward Parker said: "The decision not to aim for the summit was not an easy one, but it is the right decision to be made. The team are very low as they have worked so hard over the last nine months to achieve the target, but they do understand why we have made this decision and they were involved in the process."
He said the main issue was unseasonal dry and warm conditions, meaning there is not enough snow on the mountain and as a result, rocks have been loosening and falling. There has also been an increase in the number of avalanches.
The team has been led by Martin Hewett, 31, from Widnes in Cheshire, a former captain in the Parachute Regiment, who was shot twice through his right shoulder in Afghanistan in 2007, which paralysed his arm.
The rest of the team is made up of Captain Francis Atkinson, Captain David Wiseman, Private Jaco van Gass and former private Karl Hinett.
Capt Wiseman, 29, from Tadcaster, North Yorkshire, was shot in the chest during a firefight with the Taliban in Afghanistan in November 2009.
Capt Atkinson, 31, from Swindon, Wiltshire, suffered a gunshot wound to his right upper arm while serving as a doctor in Afghanistan. It caused significant nerve damage, and as a result his right hand does not function properly.
North Pole trekker Pte van Gass, 25, from Middleburg, South Africa, had his left arm blown off when he was hit by a rocket-propelled grenade (RPG) in Afghanistan.
Mr Hinett, 25, from Tipton, West Midlands, sustained 37% burns to his hands, legs, arms and face when his Warrior tank received a direct hit by a petrol bomb in Basra, Iraq, in 2005.
Walking With The Wounded raises money to help other injured servicemen and women readjust to civilian life after they leave the armed forces.
Mr Parker said last Friday the team missed two rock falls by a matter of minutes and last week a group travelling with the soldiers narrowly avoided an avalanche.
He added that Mr Brice commented to him that sending Sherpas through the Khumbu icefall every day, to take supplies to the Walking With The Wounded team, felt like "sending them off to battle".
A Sherpa from another team was killed in the icefall, which Capt Hewitt described as being at its "most dangerous" state in a decade.
He has been writing an expedition diary but admitted he kept the full scale of the dangers being faced by the team from their families, so as not to worry them.
In his diary, he wrote: "Avalanches in this area are not uncommon during the warmest hours of the day when temperature change causes expansion or contraction of the ice resulting in avalanche.
"We've witnessed avalanches at all hours including many at nightfall. Despite attempts to minimise the risk to climbers we've had narrow escapes from direct hits as we've passed through.
"Since the beginning of the climbing season the core temperature has been significantly higher than it should be for this time of year. With an unseasonably warm core temperature comes a significantly greater risk of avalanche, which we have witnessed to one degree or another most days at some point along the route to Camp 2.
"As the season progresses it will continue to get warmer and the ice field will become more unpredictable and put climbers' and Sherpas' lives at greater risk."
He added: "Whilst other smaller teams may go on and some may summit this year, our team is large and has a significant logistical tail, thus requiring many trips through the dangerous areas of this mountain and greater risk.
"I write this blog gutted that we have not completed the task we were set 10 months ago but proud to be the manager of such a determined, courageous group of men that have pushed the boundaries of endurance overcoming injury and adversity.
"The mountain is still there and we are still young! To all our partners, supports, families and friends I'd like to say thank you for your support. We'll be home soon and we will continue to provide more examples of overcoming injury in extreme environments. Support the walk."
Pte Van Gass said: "Of course we are bitterly disappointed not to be making a further attempt on the summit. I am more than gutted; however I completely understand and have been involved in the decision-making process."
The team will depart for the UK after a scheduled live broadcast from Everest on Thursday.