By Jasper Copping, The Telegraph, UK

“Proceedings are also under way in the Cayman Islands, where Mr Slutsker is seeking reinstatement as a beneficiary of the trust”

The Russian oligarch Vladimir Slutsker has lost a legal battle with his ex-wife Olga for a half share of the £40m London home they bought using an offshore trust.

When Russian oligarch Vladimir Slutsker brought a multi million pound London home with his then wife Olga using an offshore investment trust, it must have seemed like good financial sense.

But the businessman and former Russian MP is now counting the cost after losing a legal battle with his now ex-wife for a half share of the property – now worth £40m.

A judge at the High Court in London has ruled in Mrs Slutsker’s favour, in a move that could deter wealthy individuals using such trusts to own property.

The couple bought the home in South Kensington in 2000 for £6 million via an investment vehicle and the property was owned by a Cayman Islands trust, called the Misha Trust after their son.

It was set up by for the benefit of both parents and their children. However, following the breakdown of their marriage, Mrs Slutsker, 48, – who was named as “settlor” of the trust – had her husband excluded as a beneficiary so that he had no interest at all in the house.

Mr Slutsker, 56, has been involved in a long running legal battle against his ex-wife ever since, insisting he is entitled to a half-share of the property.

Both figures have formidable sporting and business backgrounds. Mrs Slutsker, a fencing champion, married her husband, a karate expert, in Russia in 1990.

While Mr Slutsker, who made a vast fortune through his ownership of Russian investment vehicle Finvest, pursued his political career as a member of the Russian Federation Council, his wife launched a gym in Moscow. Using her husband’s money, she developed the business into Russia’s largest a chain of fitness clubs.

In 2000, they bought their London home in The Boltons – the capital’s second most expensive street after Kensington Palace Gardens – after an attempt on Mr Slutsker’s life and so their son, Misha, born a year earlier, could have an English education. They had another child, Anna, in 2003.

The home was bought using joint family assets and Mrs Slutsker used profits from her health clubs to convert the property from four flats into a family home.

The couple were divorced in Russia in 2009 and have been through a series of legal battles over the fate of the property. Proceedings are also under way in the Cayman Islands, where Mr Slutsker is seeking reinstatement as a beneficiary of the trust.

Under Russian family law, Mr Slutsker, who was described by Forbes magazine as a supporter of President Vladimir Putin and a peer of Roman Abramovich, the Russian oligarch and owner of Chelsea FC, insists that – regardless of the trust – he should be recognised as 50 per cent beneficial owner of the house as the couple’s joint money had been used to buy it.

However, dismissing his pleas, Lord Justice Lloyd said that Mr Slutsker had consented to the creation of the trust with his eyes open and was bound to suffer the consequences.

The judge, sitting with Lord Justice Patten and Lady Justice Black, acknowledged that Mr Slutsker did not know the finer details of the trust and did not realise that his rights as a beneficiary could be “extinguished” on his wife’s say-so.

But the judge said the businessman was aware that the house was being bought through a trust and that the ownership structure was inconsistent with straightforward Russian law principles of joint family property. As such, Mr Slutsker knew enough about what was happening to give his “effective consent” to it.

Ruling that Mr Slutsker’s arguments were simply “wrong” under both English and Russian law, the judge said he had in any event left it too late to challenge the ownership structure.

After an earlier hearing in the dispute, High Court judge, Mr Justice Underhill, accepted that Mr Slutsker’s exclusion from any interest in the house “may seem harsh”, much of the money used to buy it having been generated from his business.

However, he said it had never been Mr Slutsker’s intention to use the house as his primary home and his ex-wife’s continued occupation of the house, with their children, was consistent with the former couple’s intentions at the time of the purchase.

In 2011, Mrs Slutsker won a Russian court fight with her ex-husband for custody of their children – after claiming that her husband spoiled them by letting them play computer games and watch cartoons all the time, and alleging that the heavily-guarded Moscow home where he kept them was “like a prison camp”.