TOKYO, JAPAN — Washington will operate “undaunted and unafraid” throughout Asia, including the Taiwan Strait, US Vice President Kamala Harris said Wednesday as she addressed American troops in Japan.

Speaking after attending Tuesday’s funeral for assassinated former Japanese leader Shinzo Abe, Harris accused China of “disturbing behaviour” in the East China Sea and South China Sea and “provocations across the Taiwan Strait”.

“The United States believes that peace and stability in the Taiwan Strait is an essential feature of a free and open Indo-Pacific,” she said, using Washington’s term for the Asia-Pacific region.

“We will continue to fly, sail and operate, undaunted and unafraid, wherever and whenever international law allows,” she added.

Beijing claims both democratic Taiwan and the narrow body of water separating the island from mainland China — one of the world’s busiest shipping channels.

The United States has long used “freedom of navigation” passages through the Taiwan Strait to push back against Chinese claims, and Western allies have increasingly joined these operations.

Harris restated Washington’s longstanding opposition to any unilateral attempt by Beijing to take control of Taiwan and pledged ongoing US support for the island’s self-defence.

In recent months, US President Joe Biden has said American troops would come to Taiwan’s aid in the event of a Chinese invasion, despite Washington’s official policy of “strategic ambiguity” on the matter.

The White House has said there is no change to that policy and Harris did not address Biden’s comments in her remarks to troops on the USS Howard at the Yokosuka Naval Base outside Tokyo.

She also slammed Russia for “attempting to annex the territory of another sovereign nation” in a reference to votes organised by Moscow in occupied areas of Ukraine.

And she accused North Korea of threatening regional stability with fresh missile launches.

Washington “does not seek conflict with China”, Harris said, but “we anticipate continued aggressive behaviour from Beijing as it attempts to unilaterally undermine the status quo”.

Harris leaves Japan later Wednesday for South Korea, where she will visit the Demilitarized Zone.