Jail-sentenced billionaire Mehmet Karamehmet is being sued for almost $10m (£6.6m) in the High Court over loans issued to Maltese shipping company Blue Shipping.
In the latest high-profile example of British courts being used to settle international commercial disputes, Commerzbank has named Karamehmet as the defendant in a case over unpaid debts. This adds to the woes of a businessman who was sentenced to seven years in prison by an Istanbul court earlier this year.
According to papers seen by The Independent on Sunday, Blue Shipping is alleged to have failed to pay loan instalments worth £765,000 on 7 February and £765,000 in May 2013.
Karamehmet is best known as the founder of Turkey's biggest phone company, Turkcell. He is one of the world's richest men with an estimated fortune of $2.4bn, according to Forbes.
The news comes just days after Karamehmet won a long-running legal battle against Russia's Alfa Group over control of Turkcell.
The UK Privy Council ruled last Tuesday that Karamehmet's Cukurova group must pay $1.56bn to re-acquire control of Turkcell from the Alfa Group of the Russian oligarch Mikhail Fridman. Cukurova, which is Karamehmet's holding company, is registered in the British Virgin Islands – which is why the case is being dealt with by the Privy Council. This is the final court of appeal for many Commonwealth countries.
Karamehmet was sentenced to seven years in prison over loans issued under his watch while at Pamukbank, a private bank of which he was deputy chairman. He was previously sentenced to 11 years in 2010, although this was later overturned by Turkey's court of appeal. The sentence has yet to take effect.
The dispute between Commerzbank and Karamehmet is the latest international dispute to be brought to Britain.
In May, it emerged that Ukrainian billionaire Viktor Pinchuk was suing two of his compatriots in the High Court, claiming they failed to hand over an iron ore business for which he paid $143m.
Mr Pinchuk claims he agreed to buy the factory in the city of Kryvyi Rih from Gennadiy Bogolyubov and a second oligarch in 2004, but they didn't transfer it after being paid. Mr Bogolyubov said he will fight the claim.