A U.S. Navy patrol aircraft flew through the sensitive Taiwan Strait on Wednesday, the U.S. military said, describing the mission as a demonstration of the country's commitment to a free and open Indo-Pacific.

 A P-8A Poseidon assigned to the "Skinny Dragons" of Patrol Squadron (VP) 

China claims sovereignty over democratically governed Taiwan, and says it has jurisdiction over the strait. Taiwan and the United States dispute that, saying the Taiwan Strait is an international waterway.

The U.S. Navy's 7th Fleet said the P-8A Poseidon maritime patrol and reconnaissance plane, which is also used for anti-submarine missions, flew over the strait in international airspace.

"The aircraft's transit of the Taiwan Strait demonstrates the United States' commitment to a free and open Indo-Pacific. The United States military flies, sails and operates anywhere international law allows," it said in a statement.

Taiwan's defence ministry said its forces monitored the U.S. aircraft as it flew in south through the strait, and described the situation as "normal".

There was no immediate comment from China.

The last time the U.S. Navy announced a Poseidon had flown through the strait, in October, China said it had sent fighter jets to monitor and warn the aircraft.

Taiwan is gearing up for presidential and parliamentary elections on Jan. 13, which China has cast as a choice between war and peace.

China has stepped up its military activity around Taiwan in the past four years, including staging two rounds of major war games over the last year and a half.

US officials to visit Taiwan to explain chip curbs, minister says.

Taiwan Economy Minister Wang Mei-hua.

U.S. officials plan to visit Taiwan to explain to companies details of new curbs, primarily aimed at China, on advanced chip exports, the island's economy minister said on Monday.

The Biden administration in October said it plans to halt shipments to China of more advanced artificial intelligence chips designed by Nvidia and others, as part of measures to try to stop Beijing from receiving U.S. technologies to strengthen its military.

Taiwan, home to the world's largest contract chipmaker TSMC and many other semiconductor firms, has its own restrictions on what can go to China, which claims the democratically-governed island as its own territory.

Taiwan Economy Minister Wang Mei-hua said some details of the extremely long new U.S. rules needed explanation.

"We think that them (the U.S.) coming to Taiwan, to explain things to companies, getting a face-to-face understanding of the thinking of U.S. enforcement agencies, having on site communication on the details, is something Taiwan needs," she told reporters.

Given the concentration of chip making in Taiwan it was "advantageous" for Taiwanese companies to hear the details of the new controls from the U.S. officials, Wang said.

Taiwan's official Central News Agency said the U.S. officials, who it did not name, would visit Taiwan next month and hold events in the chip hubs of Hsinchu and Tainan.

The U.S. Commerce Department did not respond to requests for comment outside business hours.