TAIPEI: The United States announced Wednesday its highest-level visit to Taiwan since it switched diplomatic recognition to China in 1979, a move Beijing blasted as a threat to "peace and stability".

The visit, headed by health chief Alex Azar, comes as relations between the world's two biggest powers plunge to historic lows.

"This marks... the first Cabinet member to visit in six years, and the highest level visit by a US Cabinet official since 1979," said Washington's de facto embassy, the American Institute in Taiwan, with no date yet given for the visit.

Washington remains the leading arms supplier to the island but has historically been cautious in holding official contacts with it.

Beijing views Taiwan as its own territory - vowing to one day seize it - and bristles at any moves by other countries to recognise or communicate with Taipei.

"China firmly opposes official exchanges between the US and Taiwan," Wang Wenbin, a spokesman for China's Ministry of Foreign Affairs, said as he called for the visit to be cancelled.

"We urge the US to abide by the one-China principle... to avoid seriously endangering Sino-US relations, as well as peace and stability across the Taiwan Strait."

Taiwan said Azar would meet President Tsai Ing-wen.

"(The) timely visit is another testament to the strong Taiwan-US partnership based on our longstanding friendship and shared values," Tsai wrote on Twitter.

Relations have warmed dramatically under President Donald Trump, who has used embracing democratic Taiwan more closely as a way to hit back at authoritarian Beijing as he clashes with China on a host of issues, including trade and coronavirus.

Taiwan's success at stopping its own virus outbreak - and its emergence as one of Asia's most progressive democracies - has also earned the island growing bipartisan support in Washington.

"The Trump administration is increasing its relations with Taiwan to a record-high level, sending a message to China that the US will not sacrifice Taiwan for its relations with China," Eric Huang, an international relations analyst at Tamkang University in Taipei, told AFP.

Shortly after Trump's election win in 2016, Tsai phoned to congratulate him, making him the first president - sitting or newly elected - to speak directly with a Taiwanese leader since 1979.

Taiwan is massively outgunned by China and Trump's administration has sold a number of big-ticket military items - including fighter jets - that previous presidents more wary of angering Beijing had balked at.