Tensions are rising in the disputed South China Sea, where a Chinese survey vessel has been tagging an exploration ship which Malaysia’s state oil firm Petronas is operating in the area, security sources in the region told Reuters on Friday.

The long-running dispute in the South China Sea involves territorial claims by China as well as Vietnam, the Philippines, Taiwan, Brunei, and Malaysia. China has territorial claims to about 90 percent of the South China Sea, which has put it at odds with its neighbors.

The Chinese research and survey vessel Haiyang Dizhi 8 was close to Malaysian waters, and at one point on Friday, the Chinese ship was flanked by Chinese ships of the coast guard and maritime militia, according to Reuters’ sources. The Haiyang Dizhi 8 ship was close to the West Capella exploration vessel operated by Petronas.

The same Chinese ship was spotted off Vietnam’s waters earlier this week, and moving closer to Malaysia, according to ship-tracking data cited by Reuters on Thursday.

At the end of last year, the Chinese and Philippine foreign ministers sealed an agreement for the two countries to pursue joint oil and gas exploration in the South China Sea. The talks between the two countries on the South China Sea’s oil and gas potential and how to exploit it had been going on for years. An agreement has proved challenging to reach, however, mostly because of China’s territorial claims to the basin, which cover nearly the entirety of it.

But tensions in the South China Sea have increased in recent weeks.

Last week, the U.S. State Department said, commenting on reports that China had sunk a Vietnamese fishing vessel in the South China Sea:

“We call on the PRC to remain focused on supporting international efforts to combat the global pandemic, and to stop exploiting the distraction or vulnerability of other states to expand its unlawful claims in the South China Sea.”

By Tsvetana Paraskova for Oilprice.com

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