Sir James Dyson, the billionaire investor, has played down concerns that a “hard Brexit” could harm the UK economy by claiming that World Trade Organisation tariffs have not prevented his technology company from achieving record financial results.

Dyson said that WTO tariffs – which range from 5% to 10% – had “not held us back at all” and were a “tiny penalty to pay” for trading with Europe.

Other business leaders have warned that the UK economy would be hurt by a “hard Brexit” from the single market and the introduction of WTO tariffs on trading with Europe. They have claimed that the extra cost of importing and exporting goods would make businesses uncompetitive.

Dyson was speaking as his technology company published record annual financial results for 2016. Sales rose 45% year-on-year to £2.5bn for 2016 while underlying profits rose 41% to £631m.

The results include a 244% rise in sales in China while UK sales rose by a third. Popular products included Dyson’s new V8 cordless vacuum cleaner – its fastest-selling vacuum cleaner ever – and its first hairdryer, the supersonic, which was the second most sold item on John Lewis’s website before Christmas, behind chocolate coins.

Dyson pays WTO tariffs because it manufactures products in Singapore then exports them around the world, including to Europe.

Dyson, a prominent supporter of Brexit before last year’s referendum, said: “They have not held us back at all. It is clearly not a barrier to exporting into Europe.”

The investor said that the tariffs were a “tiny penalty to pay” compared to other taxes such as corporation tax.



However, he also said that he did not expect the UK to have to fall back on WTO tariffs. “I don’t believe it will get to that, it’s not in Europe’s interests,” he said.

As part of any Brexit deal Dyson wants Theresa May, the prime minister, to remove foreign students from official immigration figures and particularly protect those studying maths, engineering and science.

“I wouldn’t want the government to target that area. We should make maths, science and engineering students that come to stay in this country welcome here,” he said.

The tycoon said that the drop in the value of sterling since the referendum has led to Dyson putting up the price of some of its products, although he said the increases varied product-by-product and declined to provide further details.

“It [the drop in the value of sterling] is not good news for anyone who imports products,” he said.

Dyson is planning further expansion by opening 25 new shops around the world, including one on Fifth Avenue in New York. The company, which employs 3,500 engineers and scientists, has also committed to a significant expansion in the UK by opening a new 517-acre campus near its base in Wiltshire.

The campus is part of a £2.5bn investment into developing new battery technologies and robotics. The size of the campus and the company’s work on batteries, robotics and artificial intelligence, has increased speculation that Dyson is developing a driverless electric car, but Dyson has declined to comment on this.