Arkady Gaydamak, the wealthy father of the former Portsmouth FC owner Sacha, yesterday lost the latest stage in his $2bn High Court battle against former business partner and so-called King of Diamonds, Lev Leviev.
It is a bitter blow for the colourful tycoon who has also taken legal action against Russia's top rabbi over the case.
The two millionaires have been at war for years over ownership of their lucrative diamond venture in Angola, with Mr Gaydamak claiming Mr Leviev effectively stole his half of the operation.
Mr Leviev, who lives in London, is one of the world's biggest diamond businessmen. He famously suffered one of the biggest heists in history at Cannes last year when a lone gunman walked into an exhibition of Leviev diamonds and stole an estimated £88.5m-worth of booty.
Mr Gaydamak, meanwhile, is best known in France for being implicated in the Angolagate scandal, in which former interior minister Charles Pasqua and late-president Francois Mitterand's son Jean-Christophe were alleged to have been involved in supplying arms to the Angolan government during the civil war, in breach of sanctions.
Mr Gaydamak was convicted over Angolagate by a French court in 2009, by which time he had gone on the run. He was sentenced to six years in prison. However, in 2011, the charges relating to the Angola affair were dropped and his jail term reduced to three years for money laundering and tax fraud. He remains a fugitive from France and has not come to the UK since as he would probably be extradited.
The row between the two men goes back to 2001, when, as controversy raged around him in France and elsewhere, Mr Gaydamak claims, he agreed for Mr Leviev to be the public face of his half of their lucrative diamond business in Angola, keeping his own 50 per cent stake secret. The pair signed a contract which Russia's Rabbi Berel Lazar kept for safekeeping –traditional in some Jewish business circles. The rabbi later apparently lost or destroyed it.
Hundreds of millions of dollars flowed from Mr Leviev to Mr Gaydamak under this arrangement until around 2005, when the funds stopped. Mr Gaydamak sued in London's High Court.
However, in August 2011, before the first London court case had begun, Mr Gaydamak travelled to Angola where senior officials convinced him to sign a settlement ending the venture with Mr Leviev. Those officials, Mr Gaydamak said, made it clear that he would be compensated by Mr Leviev and be granted a passport and diplomatic immunity by the Angolan government. However, he alleged, those promises transpired to be false.
In that first case heard in 2012, Mr Leviev denied there was any agreement made in 2001 – a denial the judge did not believe. But, crucially, Mr Justice Vos also found against Mr Gaydamak's claim that he had been duped into signing the settlement agreement under false pretences. The Angolan official had given no firm guarantees of compensation, the judge ruled, killing off Mr Gaydamak's claim.
Mr Gaydamak, however, last autumn returned to the High Court with another case, this time including the senior Angolans and claiming Mr Leviev had breached the trust in which he was held from the original 2001 deal. Mr Justice Mann, however, held that the settlement agreement still stood, and struck out Mr Gaydamak's claim.
Clive Zietman, the Stewarts Law partner acting for Mr Leviev said: "This second case was misconstrued, totally without foundation and has now been struck out."
Lawyers for Mr Gaydamak did not return calls. Mr Gaydamak could try to pursue his case further in the Supreme Court.