A Chinese state-run oil company’s offer of tenders to foreign partners for nine oil blocks in the South China Sea has triggered a protest from Vietnam, amid rising tensions between China and several of its neighbours over the disputed region.

Vietnam, which had earlier angered China by entering into joint exploration projects with India and Russia, described the offer from the China National Offshore Oil Corporation (CNOOC) as “illegal”.

Earlier, its ambassador in Beijing had been summoned after the Vietnamese National Assembly passed a law asserting claims over disputed islands in the South China Sea.

CNOOC, China’s third biggest oil company, announced this week it would issue tenders seeking joint exploitation of nine blocks, stretching over 160,000 square kilometres, against the backdrop of tensions with Vietnam and the Philippines following a stand-off between ships at the Scarborough Shoal.

Vietnam, which asserts claims over some of the blocks, said it “strongly protests” the offer by CNOOC. The Foreign Ministry, in a statement, said the blocks were located within Vietnam’s 200-nautical-mile exclusive economic zone.

Chinese Foreign Ministry spokesperson Hong Lei told reporters the tender was only “a normal business activity”, when asked if the CNOOC move would heighten prevailing tensions.

“China and Vietnam have reached many agreements regarding the settlement of maritime disputes,” he said. “We hope Vietnam will respect these agreements and avoid taking any action that may complicate the matter. China’s position on disputes regarding the South China Sea remains unchanged. We are committed to properly settling disputes through negotiations and joint exploitation.”

But only few months ago, China strongly hit out at moves by Vietnam to take forward joint exploration projects with India and Russia. Oil and Natural Gas Corporation (ONGC) Videsh subsequently suspended operations in the two blocks, located within Vietnam’s exclusive economic zone, after it found that the hydrocarbon resources did not merit the investment.

Wu Shicun, president of the official National Institute for South China Sea Studies, a think-tank which advises the government on the South China Sea dispute, said in a recent interview it was China’s view that 40 per cent of the two blocks, 127 and 128, were within the area denoted in Chinese maps by a U-shaped line where China held claims. Mr. Wu alleged it was “Vietnam’s maritime strategy to try and invite international oil companies and governments to get involved”, and that Beijing “will not stand any joint cooperation in our claimed maritime area”.

Now that China’s own CNOOC has stirred the sea’s waters with its offer of blocks that Vietnam has claims on for joint projects, it remains to be seen how foreign companies will respond.

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