Beijing says Hanoi bears full blame for incident and tells it to end provocation

Maritime tensions have escalated, with China demanding that Vietnam stop its policy of harassment in the South China Sea following the sinking of a Vietnamese fishing boat.

China has also rebutted comments made by Japan regarding the Xisha Islands and announced the relocation of an oil rig, whose deployment this month led to deadly anti-China riots in Vietnam.

The rig has been moved for second-phase operations that analysts said had long been planned.

The Vietnamese fishing boat sank close to the rig. Chinese Foreign Ministry spokesman Qin Gang said Vietnam bore sole responsibility with its "insistence on forcefully disrupting China's normal operations and its dangerous actions on the sea".

All 10 crew members from the boat were rescued after the sinking on Monday evening about 31 km from the rig.

China said the Vietnamese vessel deliberately rammed a fishing boat before sinking.

Vietnam claimed that some 40 Chinese fishing boats had surrounded its vessel before one of them rammed it and the boat sank.

"We urge the Vietnamese once again to immediately stop all disruptive and damaging activities," Qin said. "As for how the situation will develop and how China will react, it depends on what Hanoi does."

Vice-Minister of Foreign Affairs Liu Zhenmin reiterated on Tuesday that China would continue to pursue the peaceful settlement of disputes through negotiations.

He said no country should doubt China's determination and will to safeguard the peace and stability of the South China Sea.

Qin said Chinese enterprises had been exploring for oil in waters near the Xisha Islands for more than a decade.

"China's drilling and exploration activities, all conducted in undisputed Chinese coastal waters, are reasonable and legal," he said. Qin also urged Japan to stop making "irresponsible" remarks. He was commenting after Japanese Chief Cabinet Secretary Yoshihide Suga said in Tokyo, "It is important for the countries concerned to refrain from unilateral action that would raise tensions, and to handle matters calmly, while observing international law."

Qin said China had resumed sovereignty over the Xisha Islands after World War II following Japan's occupation, a fact Tokyo did not challenge.

"We are doing our own things in our waters without provoking anyone, but instead we were disrupted and irresponsibly judged by some countries. China cannot accept that," he said.

Vietnamese vessels have routinely engaged in maritime harassment to disrupt oil drilling, according to the Chinese Foreign Ministry.

Media reports in Vietnam said Hanoi was planning to make a case against China to an international court. Beijing sees such a move as escalating tensions and an attempt to internationalize the issue. The Xisha Islands have been well documented over the centuries as being within Chinese territorial waters.

The oil rig, which has completed the first phase of its operations, is being moved for the second phase, which is due to end in mid-August.

Fang Yinxia, a researcher at the Second Institute of Oceanography under the State Oceanic Administration, said moving the rig was part of the exploration plan, rather than a temporary measure forced by the current situation.

"China Oilfield Services has a comprehensive drilling and exploration plan, but both of the drilling areas are within Chinese territorial waters," Fang said.

"China started drilling operations in Xisha waters as early as the 1990s," she added.

Li Guoqiang, deputy director of the Center for Chinese Borderland History and Geography at the Chinese Academy of Social Sciences, said the continued Vietnamese harassment was not just aimed at disrupting Chinese enterprises, but to claim sovereignty over Chinese waters.

An Baijie contributed to this story.