SYDNEY (REUTERS) - A Chinese helicopter has reached a Russian ship stranded in Antarctica for nine days and is beginning to pick up 52 passengers who spent Christmas and the New Year trapped in ice, the expedition leader said on Thursday.

The helicopter from the Chinese icebreaker Snow Dragon will take all the passengers from the ice-bound Akademik Shokalskiy and transfer them to an Australian Antarctic supply ship, the Aurora Australis.

Chris Turney, the leader of the private expedition, said conditions had improved enough to mount the rescue after days of blizzards, fog and shifting sea ice.

"The Chinese helicopter has arrived @ the Shokalskiy. It's 100% we're off! A huge thanks to all," Turney posted on Twitter.

Television pictures showed the helicopter checking out a makeshift landing pad on the ice then apparently picking up the first group of 12 passengers.

The Russian ship left New Zealand on Nov. 28 to commemorate the 100th anniversary of an Antarctic journey led by famed Australian explorer Douglas Mawson.

It became trapped on Dec 24, 100 nautical miles east of French Antarctic station Dumont D'Urville and about 1,500 nautical miles south of Australia's southern island state of Tasmania.

Everyone on board was believed to be in good condition and they were never in any great danger.

The Chinese ship got within sight of the Akademik Shokalskiy on Saturday, but turned back after failing to break through the ice, which was more than 3 metres thick in some place.

Two other vessels, Australia's Aurora Australis and a French flagged ship, also tried to help but failed to reach the ship because of strong wind and heavy snow.

Earlier on Thursday, the Australian Maritime Safety Authority which is coordinating the rescue, had said the rescue had again been thwarted by ice and bad weather.