LONDON, Feb. 23 (Xinhua) -- British business groups warned on Monday that a new 15 percent global tariff announced by U.S. President Donald Trump could raise costs for British exporters and add fresh strain to transatlantic trade.
The move followed a U.S. Supreme Court decision that invalidated the legal basis for a set of sweeping tariffs introduced under the 1977 International Emergency Economic Powers Act (IEEPA), a key pillar of Trump's so-called "reciprocal tariffs" as part of his "Liberation Day" trade agenda.
In response to the ruling, Trump invoked Section 122 of the 1974 Trade Act to impose a new 15 percent tariff on a wide range of imports. While some countries saw duties lowered compared with previous levels, the UK and Australia are among those that now face higher effective rates.
William Bain, head of trade policy at the British Chambers of Commerce (BCC), said the move amounts to a 5 percent increase in tariffs on a wide range of UK goods shipped to the United States, except those products covered by the Economic Prosperity Deal (EPD) with Washington.
"This will raise the tariff cost on UK exports to the U.S. by between 2 billion and 3 billion pounds (2.7 billion and 4.05 billion U.S. dollars)," Bain said.
"The 40,000 UK companies exporting goods to the U.S. will be dismayed at this latest turn of events," he added.
The U.S. remains the UK's largest single trading partner, making any tariff adjustment particularly sensitive for British exporters.
Over the past year, London secured a reduction in duties under the EPD, and business leaders said it remains critical that the agreement is fully honored.
Sean McGuire, Europe and International Director at the Confederation of British Industry (CBI), said that the direct impact could be limited if the United States maintains the terms of the deal.
But he warned a rise from 10 percent to 15 percent would "erode margins, reduce the competitiveness of UK goods in the U.S. market, and place further pressure on exporters already navigating a more fragmented and unpredictable global trading environment."
Although the Supreme Court ruling clarified the limits of presidential authority under the 1977 law, business groups note that Trump retains other legal tools to adjust tariffs. The new 15 percent rate must be approved by Congress within 150 days, leaving room for further political maneuvering.
According to Bain, the ruling also raises questions about whether U.S. importers may reclaim previously paid levies and whether British exporters could benefit from any rebates, depending on commercial terms.
For now, as British firms face heightened uncertainty amid geopolitical tensions, supply-chain fragmentation, and slowing global growth, analysts say sustained higher tariffs could weigh on UK exports and broader transatlantic trade flows. ■