The drills are conducted annually on the Taiwan-administered Itu Aba Island (Taiping Island, 太平島), said Shih Yi-che (施義哲), the administration’s head of communications.
In 2008, Taiwan built a 1,150m-long airstrip on the islet, which is known as Ba Binh in Vietnam and is also claimed by China. Aside from these three competing claims, all or parts of the Spratlys are also contested by Malaysia, Brunei and the Philippines.
The Vietnamese Ministry of Foreign Affairs on Monday said the drills violate Vietnam’s sovereignty, threaten maritime security and add to tensions in the area.
Ministry of Foreign Affairs spokeswoman Anna Kao (高安) did not immediately return two calls to her office, while Shih said he was not aware of the complaint.
Democratic Progressive Party Legislator Chiu Chih-wei (邱志偉) said by telephone yesterday that Taiwan must strengthen its military presence on Taiping, given China’s land reclamation in the Spratlys.
Beijing has been carrying out land reclamation projects in both the Spratlys and Paracels (Xisha Islands, 西沙群島) — which Taiwan claims — as it seeks to extend the reach of its military in one of the world’s busiest waterways.
A legislative committee last week commissioned a study on the possibility of stationing warships on Taiping, while the government has earmarked NT$3.3 billion (US$110.24 million) to build a new wharf there.
China has been more aggressively asserting its territorial claims to more than 90 percent of the waterway, disregarding the multiple claims of sovereignty.
It completed an upgraded airstrip in the Paracel Islands last month, prompting a similar complaint from Vietnam.
Hanoi was also angered earlier this year when Beijing moved an oil rig into waters off its coast, prompting weeks of skirmishes between vessels from both sides and leading to deadly anti-China riots in Vietnam in May. China removed the rig in July.
Taiwanese firms were also affected by the riots, apparently because rioters mistakenly thought they were Chinese-owned.
Taiwan is the fourth-largest foreign investor in Vietnam. Last year, Vietnam had a US$7.2 billion trade deficit with Taiwan, according to Hanoi government data.
Taiwanese investment in the country reached US$723.4 million in the year through last month.