The US billionaire real estate magnate Charles Cohen has lost control of his upmarket UK cinema chain after an escalating legal battle over unpaid debts.

Curzon, the historic arthouse chain that has 16 venues across the UK, has been snapped up by the US private equity firm Fortress Investment Group.

Terms of the deal were not disclosed, but Fortress reportedly offered $5m (￡3.9m) for the cinema group.

Curzon, which is one of the oldest cinema chains in Britain, was put up for auction earlier this year after its previous owner, Cohen Media Group, was ordered by a New York judge to sell off some of its assets.

Fortress, which owns Majestic Wine and Poundstretcher, sued Mr Cohen’s business empire after it defaulted on a $534m loan, with the tycoon also on the hook for more than $187m in personal guarantees.

The Curzon auction included the cinema group’s distribution arm, Artificial Eye, as well as its home streaming service.

Mr Cohen’s US cinema group, Landmark Theaters, has also been put up for auction, while he has already lost control of an office tower in New York’s Midtown.

But the legal dispute has escalated in recent weeks after Fortress accused Mr Cohen of trying to shield his assets from the court order.

In a filing in the New York Supreme Court, Fortress alleged that Mr Cohen transferred $70m worth of assets to new owners. This included moving a $20m mansion in Greenwich, New York, into his wife’s name, and transferring ownership of at least four luxury yachts worth $50m.

Mr Cohen is appealing the judge’s ruling and for the $187m liability to be reversed in full. Cohen Media Group has been contacted for comment.

Mr Cohen bought Curzon in 2019, a year after buying Landmark Theaters in the US. The cinema chains were used as collateral on the Fortress loan, alongside the Manhattan tower, a design centre and a Florida hotel.

The acquisitions came shortly before lockdown forced widespread cinema closures and pushed the sector into crisis. Cinemas are also struggling with the shift to streaming, as attendance continues to fall short of pre-Covid levels.

Curzon was set up in 1934 by Harold Wingate, who opened his first cinema in Mayfair. It became known for introducing audiences to international cinema by importing and screening some of the first foreign language films in the UK.

Artificial Eye, which was founded in 1976, has been behind major hits including 2019 South Korean blockbuster Parasite. Curzon was also ahead of the curve on streaming, launching its home cinema streaming service in 2010.

In recent years, the chain has opened new cinemas in locations including Hoxton, Camden, Kingston upon Thames and Canterbury.