Tatiana Akhmedova accused her ex-husband, 65-year-old businessman Farkhad Akhmedov, of hiding assets, and their 27-year-old son, Temur Akhmedov, of acting as his father's “lieutenant”.
A judge on Wednesday concluded the father and son had worked together against Ms Akhmedova and that very large sums had been transferred to the couple’s eldest son.
Mrs Justice Gwynneth Knowles ordered Temur Akhmedov, a London trader, to pay Ms Akhmedova about £75m.
Ms Akhmedova said in a statement following the ruling: “Today’s judgment is the inevitable conclusion given Farkhad's failure to behave honourably in the first instance.”
Farkhad Akhmedov responded: “Entirely predictably, given its original wrong and misguided judgment, the London court has ruled in favour of visiting ‘the sins’ of the father on an innocent and loyal son.”
A spokesman for Temur Akhmedov added: “Like millions of young people, Temur has been caught up in the break-up of his parents’ marriage. He never sought to take sides or get involved but inevitably found himself sucked into the vortex of a bitter family dispute.
“His subsequent actions were only ever motivated by his desire to end the war between his parents.
“While he fundamentally disagrees with this judgment, he would consider it a price worth paying for should it lead to a reasonable settlement between the parents he both loves.”
Mrs Justice Knowles had considered evidence in the battle between mother and son at a trial in the family division of the High Court in London.
She said in a written ruling: “All happy families are alike; each unhappy family is unhappy in its own way. With apologies to Tolstoy, the Akhmedov family is one of the unhappiest ever to have appeared in my courtroom.”
Ms Akhmedova, who is from Russia but lives in London, was awarded a 41.5 per cent share of Mr Akhmedov's £1bn-plus fortune by another British judge in late 2016.
Mr Justice Haddon-Cave, who oversaw a hearing in London, said she should receive £453m – thought to be the biggest award of its kind made in Britain.
But judges have heard that she has so far received about £5m and Mr Akhmedov has not “voluntarily” paid a penny.
Ms Akhmedova says her ex-husband has tried to put assets beyond her reach and she took legal action in Britain and abroad in a bid to get hold of what she is owed.
However, Mr Akhmedov argued that, because he and his ex-wife are not British and were not married in Britain, a British judge should not have made a decision.
Ms Akhmedova has already become embroiled in litigation with a number of trusts based in Liechtenstein, into which Mr Akhmedov has transferred assets.
Mrs Justice Knowles heard how Mr Akhmedov had transferred a super-yacht, the Luna, worth around £340m, and an art collection, worth around £110m, into the ownership of trusts in Liechtenstein.
The judge said in the ruling published on Wednesday that Temur Akhmedov was dishonest, had lied, and was his “father's lieutenant”.
“The wife has been the victim of a series of schemes designed to put every penny of the husband’s wealth beyond her reach,” she said.
“Their eldest son, Temur, confirmed in his oral evidence that the husband would rather have seen the money burnt than for the wife to receive a penny of it.
“Regrettably, those schemes were carried out with Temur’s knowledge and active assistance.
“I reject his case that he was a mere go-between for his father: the evidence indicated otherwise.
“Temur told me in his evidence that he had helped his father protect his assets from his mother’s claims.
“He was, indeed, his father’s lieutenant.”
She added: “The transfers of very large sums of money to Temur in 2015 and 2016 were driven by the husband’s overarching desire to keep his assets from the wife.”
Additional reporting by PA