Passengers and some crew on a ship stuck in thick ice in Antarctica are to be taken off by helicopter once the weather permits, Russian officials say.
News of the decision came after an Australian icebreaker making a fresh rescue attempt had to turn back.
The Russian-flagged research vessel Akademik Shokalskiy has been stuck in ice for nearly a week. It is carrying 74 scientists, tourists and crew.
The ship is stocked with food and is in no danger, the team on board says.
The third attempt to rescue the vessel – by Australian icebreaker Aurora Australis – failed early on Monday because of fierce winds and poor visibility.
Chris Turney Professor of climate change, University of New South Wales
Earlier attempts by Chinese and French icebreakers to reach the ship were also foiled by the thick ice.
The Shokalskiy was trapped on Christmas Eve by thick sheets of ice, driven by strong winds, about 1,500 nautical miles south of Hobart – the capital of the Australian state of Tasmania.
“A decision has been reached to evacuate 52 passengers and four crew members by helicopter from China’s Xue Long ship, should the weather allow,” a Russian foreign ministry statement said on Monday.
Earlier the Australian Maritime Safety Authority (AMSA) said: “The area where the MV Akademik Shokalskiy is beset by ice is currently experiencing winds of up to 30 knots and snow showers.”
“These weather conditions have resulted in poor visibility and made it difficult and unsafe for the Aurora Australis to continue today’s [Monday’s] attempt to assist the MV Akademik Shokalskiy.”
The BBC’s Andrew Luck-Baker, who is on the Shokalskiy, said scientists on board thought the ice was much thicker than usual for this time of year.
The Chinese vessel, the Snow Dragon, came within seven nautical miles (11 km) of the Russian ship before stalling and being forced to return to the open sea.
The Akademik Shokalskiy is being used by the Australasian Antarctic Expedition to follow the route explorer Douglas Mawson travelled a century ago.
Despite being trapped, the scientists have continued their experiments, measuring temperature and salinity through cracks in the surrounding ice.
Those on board include 22 Russian crew. Passengers are of various nationalities, many of them Australian.
One of the leaders of the scientific expedition said via Skype that those on board were in good spirits and wanted their families and friends to know they were safe and well, AFP reported.
“It’s Antarctica, we are just taking it one day at a time,” said Chris Turney, professor of climate change at the University of New South Wales.
“The conditions are so extreme in Antarctica, you just never know. We are always hopeful.”