TAIPEI: China warned Washington not to "play with fire" on Wednesday as a US delegation wrapped up a historic trip to the self-ruled island of Taiwan.

Beijing has been infuriated by the highest-profile visit in decades to Taiwan, which it sees as part of its territory, as US-China relations plunge to a record low over a range of issues from trade to military and the coronavirus pandemic.

Health chief Alex Azar finished a three-day visit to Taiwan, during which he criticised China's handling of the pandemic and visited the shrine of a former Taiwan president hated by the Communist Party leadership.

Beijing slammed the visit Wednesday and said it "firmly opposes official exchanges between the US and Taiwan under any pretext".

"On issues involving China's core interests, some people in the US must not harbour illusions, those who play with fire will get burned," said foreign ministry spokesman Zhao Lijian at a regular press briefing.

"I would also like to remind the Taiwan authorities not to be... subservient to others, to rely on the support of foreigners, and to be bent on pursuing independence, which is a dead end," Zhao said.

Beijing insists that Taiwan - which has been self-ruled since 1949 - is part of "one China" and has vowed to react with force if it ever formally declares independence.

On the last day of the trip, Azar visited a shrine to Taiwan's late president Lee Teng-hui Wednesday, praising his role in steering the island's transition to democracy.

The US cabinet member wrote a message of condolence for Lee, who died last month aged 97.

"President Lee's democratic legacy will forever propel the U.S.-Taiwan relationship forward," Azar wrote.