TAISHAN, China — Australian officials have asked an American icebreaker to help with the rescue of Chinese and Russian vessels that are surrounded by ice floes off Antarctica, according to an announcement on Sunday by the Australian Maritime Safety Authority.

The officials said the United States Coast Guard had answered the request and was making a ship available to assist the other vessels.

The deployment of the American ship, the Polar Star, for the rescue operation adds to an increasingly complex set of issues for international vessels that have found themselves struggling against unfavorable ice and weather conditions in Antarctica.

A news release from the Australian authorities said the Polar Star, which was docked in Australia, has been en route to Antarctica since Dec. 3. Its original mission was to clear a navigable shipping channel in McMurdo Sound to the National Science Foundation’s Scientific Research Station. The channel is used by resupply ships to deliver food, fuel and other goods to the station. Australian officials said the American icebreaker would continue with that mission after the rescue operation was over.