A Chinese icebreaker that went to the aid of passengers on ship stranded in Antarctica has found itself stuck in heavy ice, further complicating the nine-day roller-coaster rescue mission.
The Akademik Shokalskiy had been retracing Sir Douglas Mawson's Antarctic expedition and conducting scientific research before sea ice stopped it in its tracks.
The 52 scientists and tourists on board the Russian ship were airlifted to safety by a Chinese helicopter on Thursday, after becoming stuck on Christmas Eve.
The helicopter was flown off the icebreaker Xue Long (Snow Dragon), which has now flagged concerns about its own ability to move through heavy ice.
The Australian Maritime Safety Authority (AMSA) says the icebreaker will attempt to move overnight.
"It will attempt to manoeuvre through the ice when tidal conditions are most suitable during the early hours of 4 January 2014," AMSA said.
The 52 rescued passengers were flown to the Australian icebreaker Aurora Australis in an operation that took more than four hours.
Australian icebreaker remains in open water
The Aurora Australis had meant to sail towards an Antarctic base to complete a resupply before carrying the rescued passengers back to Australia.
AMSA says the Aurora Australis will now remain on standby in open water in the area "as a precautionary measure".
The Australian Antarctic Division says its resources have been stretched to the limit by its diversion to Commonwealth Bay. Jason Mundy from the Antarctic Division hopes the Russian ship's insurers will foot the bill for the rescue.
"It's difficult to quantify costs in dollar terms because for us the costs are largely going to be in costs and operational terms," he said.