The US Navy has sailed a warship near the Paracel Islands in the South China Sea as part of an effort to challenge Chinese claims to the disputed waters.

The guided-missile destroyer USS Wayne E. Meyer sailed through the area without receiving permission from China, or from Vietnam or Taiwan, which claim ownership of the archipelago too.

“USS Wayne E. Meyer challenged the restrictions on innocent passage imposed by China, Taiwan, and Vietnam, and also contested China’s claim to straight baselines enclosing the Paracel Islands,” Cdr. Reann Mommsen, a spokesperson for the US Navy’s 7th fleet, said in a statement.

China, Taiwan, and Vietnam “require either permission or advance notification before a foreign military vessel engages in ‘innocent passage’ through territorial seas,” Mommsen said, adding, “the unilateral imposition of any authorization or notification requirement for innocent passage is not permitted by international law, so the United States challenged these requirements.”

The South China Sea has long been a source of tension between Beijing and Washington, which regularly dispatches its warships and warplanes to the waters as part of what it describes as “freedom of navigation” patrols.

Beijing has constantly warned the US against its military activities in the sea, saying that potential close military encounters by air and naval forces of the two countries in the region could easily trigger miscalculation or even accidents at sea or in air.

It has also urged the US on numerous occasions to stop meddling in Beijing’s territorial disputes with its neighbors which have competing sovereignty claims to the strategic waters.