By presidential executive order on June 16, 2025, the United States formally implements the General Terms of the U.S.–UK Economic Prosperity Deal, first announced May 8 by President Trump and U.K. Prime Minister Keir Starmer, according to White House's release.
The order establishes an annual tariff‑rate quota of 100,000 British‑made automobiles, which will enter the U.S. market at a combined tariff of 10 percent—7.5 percent plus a 2.5 percent most‑favoured‑nation rate—replacing the previous 25 percent tariff under Proclamation 10908.
Tariffs on automotive parts of U.K. origin will similarly be reduced to 10 percent.
Entry under the quota will begin seven days after publication in the Federal Register and will be adjusted for calendar year 2025.
Additionally, tariffs on U.K. aerospace products subject to national security tariff orders (Executive Order 14257; Proclamations 9704, 9705) will be lifted, with Commerce to publish implementing tariff schedule modifications within seven days.
Future quotas for U.K.‑produced steel, aluminum, and derivative products will be established pending U.K. compliance with U.S. supply‑chain security and foreign ownership standards. Both nations will also negotiate preferential terms on U.K. pharmaceuticals and proactively address national security concerns through supply‑chain cooperation in aerospace and aircraft manufacturing.
The executive order cites legal authority including the International Emergency Economic Powers Act, National Emergencies Act, Trade Expansion Act, Trade Act of 1974, and Title 3, section 301, U.S. Code.
Its stated purpose is to implement measures deemed necessary and appropriate to address national security and trade deficits under existing emergency and tariff proclamations.
The U.K. Department for Business & Trade published the terms on May 8.