China's icebreaker for Antarctic research Xuelong and Merchant ship Zhonghaishaohua are expected to arrive on Tuesday in waters where debris possibly linked to the missing Malaysia Airlines Flight MH370 was spotted.

More vessels are heading for the waters, Foreign Ministry spokesman Hong Lei told a daily news briefing on Monday.

Haixun 01 and Nanhaijiu 101 are approaching the southern Indian Ocean and three Chinese naval ships, including an amphibious transport dock (Kunlunshan), supply ship Qiandaohu and missile destroyer Haikou, are also heading for the waters, according to Hong.

Meanwhile, China Maritime Search and Rescue Center has coordinated merchant ships owned by Chinese shipping company COSCO and China Shipping Company to change their original courses and head for the waters, he said.

China Maritime Search and Rescue Center has coordinated merchant ships to search an area of 40,000 square kilometers, covering the Bay of Bengal and waters off Indonesia and Australia, Hong said.

China's Ministry of Agriculture has coordinated 20 fishing boats to assist in the search, he added.

China has repeatedly urged Malaysia and Australia to coordinate international efforts to conduct an all-out search in the waters and has maintained close contact with the two sides, Hong said.

Two Chinese IL-76 planes searching for MH370 off Australia returned to Perth airport on Monday.

During the mission, the crew spotted some floating objects and reported the sighting to the Australian Maritime Safety Authority, which then asked other aircraft to visit the area for further examination.

China also informed Malaysia and Australia soon after a Chinese satellite spotted a large object possibly related to the missing airplane.

The focus of the multinational search shifted to the southern Indian Ocean after Australia said on Thursday that satellite imagery identified debris in waters some 2,400 km from Perth.

Flight MH370, a Boeing 777-200ER, went missing on its way to Beijing on March 8, shortly after taking off from Kuala Lumpur. The plane was carrying 12 crew and 227 passengers, including 154 Chinese.

The search for the missing passenger jet is in its third week. Endi