WASHINGTON (AP) — The Biden administration is set to announce a more than $1 billion arms sale to Taiwan on Friday as U.S.-China tensions escalate over the status of the island, according to American officials and a congressional aide briefed on the matter.

The $1.09 billion sale includes $355 million for Harpoon air-to-sea missiles and $85 million for Sidewinder air-to-air missiles, the officials and the aide said.

They said the largest portion of the sale, however, is a $655 million logistics support package for Taiwan's surveillance radar program, which provides air defense warnings. Early warning air defense systems have become more important as China has stepped up military drills near Taiwan, which it regards as a renegade province.

The administration is to notify Congress of the sale after close of business on Friday, they said.

The administration is expected to say that the deals comply with the U.S. one-China policy and are in line with U.S. commitments to Taiwan's defense.

The acrimony and strident rhetoric between the U.S. and China over Taiwan have increased sharply since House Speaker Nancy Pelosi visited the island last month. Since Pelosi's trip to Taipei there have been at least two other congressional visits and several by governors of U.S. states, all of which China has condemned.

On Thursday, Taiwan's military said it shot down a drone hovering over one of its island outposts just off the Chinese coast in an incident that underscored the heightened tensions. A day earlier, Taiwan said it had warned off drones hovering over three of the islands it occupies off the coast of the Chinese port city of Xiamen.

China claims Taiwan as its own territory, to be annexed by force if necessary. The sides split after a civil war in 1949 and have no official relations, with China cutting off even informal contacts following the election of independence-leaning Taiwanese President Tsai Ing-wen in 2016.

Tsai's administration has pushed for a strengthening of anti-drone defenses as part of a 12.9% increase in its Defense Ministry's annual budget next year. That would boost defense spending by an additional 47.5 billion New Taiwan dollars ($1.6 billion), for a total of 415.1 billion NTD ($13.8 billion).

The U.S. described Chinese drills last month as a severe overreaction and responded by sailing two guided missile cruisers through the Taiwan Strait, which China has declared to be its sovereign waters.