The US Navy has sent a guided missile destroyer within 12 nautical miles of an island in the South China Sea which Beijing considers its sovereign territory. The move is meant as a challenge to the Chinese claim.

The USS Curtis Wilbur sailed unopposed near the Triton Island in the Paracel Islands archipelago, Captain Jeff Davis, a Pentagon spokesman, told the media. The island is administrated by China, but is also contested by Taiwan and Vietnam.

"This operation challenged attempts by the three claimants – China, Taiwan and Vietnam – to restrict navigation rights and freedoms," Davis said.

The Chinese Foreign Ministry called the sail-by illegal, saying permission from the Chinese authorities was necessary.

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The mission was part of the so-called freedom of navigation campaign, in which the US is seeking to assert its right to freely sail in the South China Sea. The region is one of the busiest maritime traffic routes, accounting for more than $5 trillion of world trade shipping annually. The US does not want to be required to seek prior permission to sail past the many islands in the sea.

"No claimants were notified prior to the transit, which is consistent with our normal process and international law," Davis said.

The US Navy conducted a similar operation in October, when it sent the guided missile destroyer Lassen to sail pass a man-made Island in the South China Sea. Beijing insists its sovereignty over the island gives it territorial rights over a 12-nautical mile zone around it.

China rebuked the move at the time, saying the US was acting recklessly and risked provoking an armed confrontation.

Several Pacific nations have conflicting territorial claims in the South China Sea. China has ramped up the pursuit of its claims in the past few years amid a military build-up.

Most of the traffic sailing through the sea is bound to or from China, which would make it the biggest loser should it be disrupted somehow.