TAIPEI, Dec. 31 (CNA) - Two US warships sailed through the sensitive Taiwan Strait on Thursday (Dec 31), the US Navy said, the second such mission this month and coming almost two weeks after a Chinese aircraft carrier group used the same waterway.

China, which claims Taiwan as its own territory, has been angered by stepped-up US support for the island, including arms sales and sailing warships through the Taiwan Strait, further souring Beijing-Washington relations.

The US Navy said the guided missile destroyers USS John S McCain and USS Curtis Wilbur had "conducted a routine Taiwan Strait transit on Dec 31 in accordance with international law".

"The ships' transit through the Taiwan Strait demonstrates the US commitment to a free and open Indo-Pacific. The United States military will continue to fly, sail and operate wherever international law allows."

This is the thirteenth sailing through the strait by the US Navy this year.

Taiwan's Defence Ministry said the ships had sailed in a northerly direction through the strait on what it termed an "ordinary mission". Taiwan's armed forces monitored the sailing and the situation is "as normal", it added.

China's Defence Ministry issued no immediate response.

China's military said it had tailed the last US warship to pass through the Taiwan Strait on Dec 19, and denounced the mission.

The day after that trip, Taiwan's navy and air force were deployed as a Chinese aircraft carrier group led by the country's newest carrier, the Shandong, sailed through the Taiwan Strait.

China said the group was on its way to routine drills in the disputed South China Sea.