Organisers of an Antarctic charity race involving Prince Harry say they are suspending its competitive element because of harsh conditions, but plan to continue the journey to the South Pole.
Harry, 29, is a member of one of three teams involving injured soldiers that set off last week on the 320-kilometre Walking with the Wounded South Pole Challenge.
Expedition director Ed Parker said the teams were experiencing "a higher degree of stress" than expected and will no longer race one another but travel and camp together.
In a recorded message on the organisation's website, Parker said the teams had had "a pretty tricky couple of days. The weather remains good but the terrain is very difficult, far harder than we had anticipated."
He said the teams would now be driven for part of the route and then finish the final 112 kilometres to the pole on foot, likely within a week.
Harry and actors Dominic West and Alexander Skarsgard are on the trek with teams from Britain, the Commonwealth and the US.
Guy Disney of the British team said there had been "a few small injuries - nothing too serious" and that the teams were determined to make it to the South Pole.
Harry, an army Apache helicopter pilot who has served in Afghanistan, spent several days in 2011 trekking with wounded servicemen on a similar expedition to the North Pole.