HANOI - Vietnam's foreign ministry has lodged a complaint with China over military drills in the South China Sea that it said were "detrimental" to Beijing's relationship with the Association of Southeast Asian Nations (ASEAN).

Vietnam and the Philippines warned of growing insecurity in Southeast Asia at a regional summit last Friday, amid concerns that China was using the cover of the coronavirus pandemic as a means to step up its activity in the disputed waterway.

On Wednesday, China began five days of drills in waters near the Paracel Islands, where Vietnam has competing claims, according to a June 27 announcement by the Maritime Safety Administration of Hainan, a large provincial island off China's southern coast.

"China's drills around (the Paracels) seriously violate Vietnam's sovereignty", foreign ministry spokeswoman Le Thi Thu Hang told a regular briefing on Thursday.

The drills "further complicate the situation, and are detrimental to the relationship between China and ASEAN," she added.

Hang said Vietnam had contacted China and delivered a diplomatic note opposing the drills.

"We request that China refrain from repeating similar actions in the South China Sea," she said.

The United States has also called on China to stop its "bullying behavior" in the South China Sea, and accused Beijing of using the COVID-19 pandemic as cover to push its territorial claims there with a surge in naval activity.

In early April, Vietnam said one of its fishing boats was sunk by a Chinese maritime surveillance vessel. China said that Vietnam's claims in South China sea are illegal and "doomed to fail".

(Reporting by Phuong Nguyen Additonal reporting by Yew Lun Tian in Beijing Writing by James Pearson; Editing by Martin Petty)