China holds live-fire exercises in Gulf of Tonkin days after Vietnam maps new territory

China's military has started live-fire exercises in the Gulf of Tonkin - after Vietnam published a map defining what it considers its territory in the body of water between the two countries.

Vietnam's foreign ministry announced the baseline - used to determine limits to territorial waters and exclusive economic zones - on Friday, saying it was to help protect and enforce its sovereign rights.

China's Maritime Safety Administration said the live-fire exercises would be focused on the Beibu Gulf area, closer to the Chinese side of the Gulf of Tonkin, and would run through to Thursday evening.

Vietnam has not publicly responded to the Chinese drills.

In March last year, China announced its baseline in the Gulf of Tonkin. In response, Vietnam said international law and the rights and interests of other countries must be respected.

Baselines are a sensitive subject in the South China Sea - where China, Vietnam and other countries in the region including the Philippines, Malaysia, Brunei and Taiwan, have conflicting claims.

The waters include two island chains - the Spratlys and Paracels - as well as a number of reefs.

China and Vietnam have long had a maritime agreement governing the Gulf of Tonkin, but have been locked in competing claims over the islands and maritime areas.

China has been growing aggressive in pursuing those claims, and in October, 10 Vietnamese fishermen were assaulted near the Paracel Islands.

China claims almost the entire South China Sea as its own, though it has not publicly released exact coordinates of its claim other than a map with 10 dashed lines broadly demarcating what it calls its territory.

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Tensions have also been high with the Philippines.

Last week, a Chinese navy helicopter flew within 10ft of a Philippine patrol plane over the South China Sea. It happened near the disputed Scarborough Shoal off the north-western Philippines. Both the Philippines and China lay claim to the reef.

(c) Sky News 2025: China holds live-fire exercises in Gulf of Tonkin days after Vietnam maps new territory