A millionaire hedge fund manager who recently came out as gay is facing one of the UK’s most expensive divorces.

Pierre Lagrange, a former trader for JP Morgan and Goldman Sachs, separated from his wife a year ago.

He was pictured with his boyfriend, the fashion designer Roubi L’Roubi, in Venice this summer.

Mr Lagrange, who is said to be worth more than £300 million thanks to his company GLG Partners, said his split from wife Catherine was amicable.

The couple filed divorce papers at the High Court last month.

The Sunday Times reports that Mrs Lagrange, a Conservative Party donor, could receive up to half of her husband’s fortune, making the divorce one of the most expensive the UK has seen.

The current record is £100 million, paid by Russian oligarch Boris Berezovsky to his former wife.

Mr Lagrange, who has invested in films such as Kick Ass, recently sold his 15-bedroom home in Kensington Palace Gardens to Chelsea FC owner Roman Abramovich for £90 million.

The Belgian-born millionaire, who says he met Mr L’Roubi after splitting from his wife, said: “My divorce reflects the reality of a separation that has happened a long time ago.

“Our divorce has been the most amicable one, with respect and love from all parties.”