Chinese vessel in the South China Sea
Representation. A Chinese vessel in South China Sea REUTERS

China asked Vietnam Thursday to immediately stop its unilateral oil exploration in disputed areas in the South China Sea and not harass Chinese fishing boats, days after Hanoi announced its plans to step up its maritime presence in the region.

Chinese Foreign Ministry spokesman Hong Lei made the comment at a daily press briefing in response to a Vietnamese Foreign Ministry spokesman's remarks Wednesday that criticized China for violating its sovereignty and accused Chinese boats of sabotaging an exploration operation that was being carried by Vietnam’s state oil firm Petrovietnam, Xinhua news agency reported.

"What the Vietnamese side said is not in accordance with the facts," Hong said.

The disputed region in question was situated near the Beibu Gulf in an area where China and Vietnam have made overlapping claims, he said, alleging that Vietnamese military vessels were driving away Chinese ships that had been conducting routine fishing activity.

"The Vietnamese side should stop the unilateral development of oil and gas in the previously mentioned areas and stop disturbing Chinese fishing ships so as to create a favorable atmosphere for negotiation," Hong said.

He added that China and Vietnam were currently in negotiations over the waters.

Last Thursday, Hanoi finalized its decision to deploy civilian-led patrols, supplemented by marine police and a border force, from Jan. 25, to stop foreign vessels that violate fishing laws within Vietnam's waters, Reuters reported citing Vietnam's government and state media.

Chinese media had recently announced new government rules authorizing police in the southern Chinese province of Hainan to board and seize foreign ships in the South China Sea, Reuters reported.

South China Sea has long been a bone of contention between China and several members of the Association of South East Asian Nations (ASEAN). China lays claim to almost the entire South China Sea including what is recognized by the U.N. as the exclusive economic zones of other neighbors, the Philippines, Vietnam, Taiwan and Brunei.

Beijing’s relations with Vietnam has grown worse in the past weeks over China’s decision to include in its revised passports an offending map, which shows Beijing staking its claim on the entire South China Sea.