China needs a permanent naval base overseas to resupply its ships contributing to the multinational anti-piracy flotilla in the Gulf of Aden off Somalia, a prominent Chinese naval researcher was quoted as saying Wednesday. The suggestion marks a further step away from China's avowed policy of not maintaining foreign military bases or alliances. Beijing says a more active naval presence abroad is necessary to protect sea lanes through which its vital foreign trade and natural resources travel. China has operated patrols for a year now in the narrow Gulf of Aden, escorting Chinese and foreign ships through waters menaced by pirates operating off the Somali coast. But coal and ore shipping lanes off the east coast of Africa have proved harder to defend. The De Xin Hai, captured 700 nautical miles east of Somalia in October, was ransomed for $4 million Sunday. The bases idea was floated in a state radio interview with Yin Zhuo, a frequent navy spokesman on matters involving interactions with foreign navies. Yin offered no suggestions on where a base would be located and said all such decisions lay with top military leaders. Such a base would provide a steady source of fresh fruit, vegetables and water, along with facilities for communications, ship repair, rest and recreation, and medical evacuation of injured personnel, Yin said.