The UK could be hit with tariffs as high as 24% if Mr Trump follows through on his threats to treat VAT as a tariff, according to Paul Ashworth, chief North America economist at Capital Economics.
Donald Trump has ordered his team to start calculating duties by early April - increasing fears of a global trade war that could also accelerate US inflation.
This is based on VAT rates combined with existing tariffs, but the Trump administration also intends to take into account regulations, government subsidies, digital services taxation policies and exchange rate policies.
The US president has promised to target countries which charge tax on US imports by matching them with a reciprocal tariff.
During a news conference afterwards, Mr Trump said India has been "very strong on tariffs" and "it's very hard to sell into India", adding: "They're going to be purchasing a lot of our oil and gas.".