Donald Trump has said he “couldn’t care less” if his tariffs push up the prices of foreign cars in America.

In comments which will increase fears of a global trade war, the US president also said the swingeing import taxes he is bringing in will be permanent.

Trump has said he plans to impose 25% tariffs on all foreign-built cars imported into the States from April 2.

The move is designed to boost the American car industry by reducing demand for foreign vehicles.

Britain currently sells more than £6 billion-worth of cars to the US, meaning the policy could have a major impact on the UK economy.

In addition, Trump wants to impose tariffs on steel imports and on all countries, like the UK, which charge VAT.

Chancellor Rachel Reeves has also been warned by the Office for Budget Responsibility that all of the spare cash she hoped to have would be wiped out if Trump goes ahead with his plans.

Asked what his message was to car bosses, Trump said: “The message is congratulations, if you make your car in the United States, you’re going to make a lot of money.

“If you don’t, you’re going to have to probably come to the United States, because if you make your car in the United States, there is no tariff.”

Asked if he was concerned about car prices going up, Trump said, “No, I couldn’t care less, because if the prices on foreign cars go up, they’re going to buy American cars.”

And asked if the tariffs would be permanent, Trump said: “Absolutely, they’re permanent, sure. The world has been ripping off the United States for the last 40 years and more. And all we’re doing is being fair, and frankly, I’m being very generous.”

Home secretary Yvette Cooper on Sunday slammed Trump’s tariffs plans.

She told Sky News: “We clearly want to see reductions in barriers to trade, not increasing barriers to trade. So obviously we’re very disappointed at the US decision to introduce tariffs, including around auto and steel and so on.”

British officials are continuing negotiations with their US counterparts in a bid to agree an economic deal which could exempt the UK from the tariffs.

The home secretary added: “In the end, if you increase barriers to trade right across the world, that’s not good for the world economy, let alone any individual country as part of that.

“That’s why our approach to this is to try to seek new trade agreements across the world, including improving our trading relationship with the EU as well as the US. This is about removing barriers instead of increasing them.”

Asked if the UK could retaliate by imposing its own tariffs on American imports, the home secretary said: “The prime minister has said that no option is off the table and we will continue to approach this in the UK national interest.”

Meanwhile, a poll by the Best for Britain campaign group showed voters want to see the government establish closer economic ties with the EU in the face of Trump’s threat.

The YouGov survey showed that 43% of of Brits believe the UK should improve trade with the bloc, compared to just 14% who think improving relations with Trump is the way to go.

Keir Starmer has said he wants to reset Britain’s relationship with the EU, but has ruled out rejoining either the single market or the customs union.