SYDNEY (AFP) - A Chinese icebreaker heading to rescue a scientific expedition vessel trapped off Antarctica has itself stalled in icy conditions, Australian media said.

"It has encountered heavy ice and it's not safe for them to continue to the Russian vessel for their own safety," an Australian Maritime Safety Authority official said, adding that the icebreaker came within six-and-a-half nautical miles of the ship.

"We'll be looking at other options today (Saturday)," she said, according to the Australian Broadcasting Corporation.