Britain's wealthiest business people are fleeing abroad amid mounting complications over tax, the country’s richest man has warned.

Amid a growing political crisis over the UK’s future relationship with the EU, Gopichand Hinduja, whose family controls a £20.6bn industrial fortune, told The Sunday Telegraph many of the country’s wealthiest people have ­already quietly left Britain for Dubai, Singapore and other financial centres.

“[In the UK] there used to be a lot of ease of doing business,” said Mr Hinduja, 78, who moved the family’s conglomerate, Hinduja Group, to London in 1980. “Now, with changes in tax – doms, non-doms – they have made so many complications that people don’t even know what returns they have to file. And I have found many of my rich friends – billionaires – have left London and become residents either in Dubai or Singapore or Lebanon.”

With annual sales of $50bn (£38.8bn), the family controls more than 50 international companies across technology, media, chemicals, oil, healthcare, banking and truck-making including Gulf Oil, IndusInd Bank, Ashok Leyland, HGS, an outsourcing company, as well as valuable real estate in the UK, India and US.

The Hinduja family was named as Britain’s second richest in May behind Sir Jim Ratcliffe, 65, founder of petrochemicals giant ­Ineos, whose fortune was valued at £21bn. In August, it emerged that Sir Jim had relocated to Monaco, promoting the Hindujas to the top of the list.