A Chinese research ship and five escort vessels were in Vietnam's exclusive economic zone (EEZ) on Friday close to gas blocks operated by Russian firms in the South China Sea, a day after Vietnam urged the ships to leave.
The Chinese vessel Xiang Yang Hong 10 began operating in Vietnam's EEZ on May 7, representing the most significant incursion since 2019, according to Ray Powell, who leads Stanford University's Project Myoushu on the South China Sea.
He said China's conduct and Vietnam's reaction were a "worrying escalation".
China claims most of the energy-rich waters of the South China Sea, including areas that are within Vietnam's EEZ.
The 2019 standoff lasted for more than three months and largely targeted a block then operated by Russian state oil firm Rosneft (ROSN.MM). Less than two years after that, Rosneft sold its assets in the South China Sea to Russia's state-owned firm Zarubezhneft, which operates some of the gas fields where the current dispute is under way.
In the last weeks since May 7, the Chinese research ship, at times flanked by a dozen vessels, has been moving largely across gas block 04-03, operated by Vietsovpetr, a joint-venture between Zarubezhneft and PetroVietnam, according to vessel-tracking data shared with Reuters by South China Sea Chronicle Initiative (SCSCI), an independent non-profit.
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