U.S. Secretary of Health and Human Services Alex Azar will visit Taiwan in coming days, his office said Tuesday, making the highest-level visit by a U.S. official in four decades — a move that angered China, which claims the island as its own.

Azar's visit will worsen already poor Beijing-Washington relations, inflamed over trade, the pandemic and human rights, even as democratic Taiwan has welcomed the show of support in the face of unrelenting Chinese pressure.

During his visit, Azar will meet with President Tsai Ing-wen, Taiwan's Foreign Ministry said, which may infuriate China further.