BEIJING, Jan. 6 -- The Chinese icebreaker that rescued 52 passengers stranded aboard a Russian ship last week is biding its time to save itself from Antarctic ice, as weather conditions may turn favorable on Monday.

Experts and scientists aboard Xuelong, or Snow Dragon, are planning three possible routes to take advantage of good weather from Monday to Wednesday, a senior official said.

"The weather conditions on Monday will decide which route to take," Qu Tanzhou, director of the Chinese Arctic and Antarctic Administration under the State Oceanic Administration, told China Daily over the phone on Sunday.

Ice floes near the vessel are up to 4 meters thick. Xuelong can break ice of 1.1 meters.

But Qu said the good news is that the ice floes are not worsening as the wind direction is changing.

Xuelong has sailed back and forth over a 1-km span to prevent it from becoming frozen in the ice, the vessel's captain Wang Jianzhong told China Central Television on Saturday.

The ship was blocked by a 1-km-long iceberg, which is drifting northwest, after it used a helicopter to rescue passengers from the Russian ship Akademik Shokalskiy and take them to Aurora Australis, an Australian supply ship in Antarctica last week. The Russian ship has been stranded in Antarctica since Dec 24.

Polar Star, the US Coast Guard's heavy polar icebreaker, was leaving Sydney, Australia, on Sunday morning to assist Xuelong and the Russian vessel.

The 122-meter US ship is able to continuously break 1.8 meters of ice at about 5.6 km per hour and 6.4 meters of ice by reversing and ramming it, according to the US Coast Guard.

Vice-Admiral Paul Zukunft of the Coast Guard Pacific Area Command said the crew is prepared to free a path for the vessels.

Everyone was hoping the two vessels would be able to get underway on their own power before Polar Star is even able to get into range, Chief Warrant Officer Allyson Conroy, spokeswoman for the Pacific Area Command, told KTUU.com, an NBC-affiliated television station serving Alaska.

Qu estimated that Polar Star can reach the stranded region on Sunday. "If Xuelong hasn't sailed out by then, Polar Star will help."

Food aboard Xuelong is enough until April and fresh water supplies are enough for 29 days, Xu Ting, deputy leader of the Chinese Antarctic expedition, told CCTV on Sunday.

Qu added that those aboard are safe and in a relaxed mood, and they can play ping-pong and watch movies.

Currently, 101 scientists and 42 crew are aboard Xuelong.

Wang said the situation is still not optimistic.

"Heavy floes and icebergs are moving fast, and a large iceberg is moving toward us," Wang told a Xinhua reporter on board on Sunday.

Xuelong was locked in a heavy floe area, some 15 km from the nearest ice-free waters, according to the Xinhua reporter.

The vessel can get out of trouble as long as it can break through the thickest floe zone, about 3.7 km long, Wang said, adding that Xuelong is waiting for the right opportunity.

Qu said icebergs and floes are being monitored 24 hours, because a collision with an iceberg may be disastrous.

The Australian Maritime Safety Authority said on Saturday that Xuelong confirmed its safety and said the ship does not require assistance at the time.

It said the Russian and Chinese ships agreed that further assistance from the Australian ship is no longer required and that they will be able to provide mutual support to each other.

The Australian ship will take the passengers rescued by Xuelong to the Australian island state of Tasmania, arriving by mid-January after refueling at Australia's Casey base in Antarctica.

On Friday, President Xi Jinping urged an all-out effort to ensure the safety of Xuelong staff.

Premier Li Keqiang has also instructed crew members aboard Xuelong to stay calm and wait for the opportunity to break out.

Xuelong left Shanghai in early November on China's 30th Antarctic expedition, which was expected to last 155 days. The mission involves scientific research, construction of the country's new research base and the site inspection of another one.

Qu said the expedition will be rescheduled after Xuelong breaks out.