Roman Abramovich will donate the "net proceeds" from his sale of Chelsea to a charitable foundation supporting Ukraine's war victims.
The Russian oligarch is selling the west London club and has vowed to support Ukraine - after the widow of murdered Russian spy Alexander Litvinenko urged him to do so.
In a statement confirming his decision to sell, Abramovich wrote: "I have instructed my team to set up a charitable foundation where all net proceeds from the sale will be donated. The foundation will be for the benefit of all victims of the war in Ukraine.
"This includes providing critical funds towards the urgent and immediate needs of victims, as well as supporting the long-term work of recovery."
His decision to sell Chelsea follows Russia's invasion of Ukraine last Thursday and the allocation of proceeds goes some way to taking the advice of Marina Litvinenko.
Ex-Russian spy Litvinenko was murdered by radiation poisoning in November 2006. He was a prominent critic of Russian president Vladimir Putin, based in the UK.
In 2015, a public inquiry into his death concluded that Putin "probably" approved his assassination.
Marina Litvinenko has campaigned against Putin since her husband's death and asked earlier on Wednesday why Abramovich suddenly wants to sell Chelsea.
"My advice is, if Abramovich wants people to see him as a human, with this money, he might donate to the Ukrainian fight for liberty, for their country, for their language, for everything," Litvinenko told The Telegraph.
She added: "I don't want to criticise and say, 'Oh, you didn't do this a long time ago.'
"But my husband was absolutely furious when he realised how easy it is for people who benefited from unfair business in Russia to receive everything in the UK.
"People just tried to close their eyes over where this money came from, but the first signal was in 2006 when my husband was killed and this radioactive polonium was used.
"How was the reaction? Not very strong. Even more since 2010, more money, more Russians are welcomed to London.
"The UK and everybody is just saying, 'oh it's a business, it's very important.
"But it was all to a bad end. Could this have prevented a Ukrainian invasion? Difficult to say... if it helps to freeze assets, we have to do it.
"If we stop short of doing something for today, we might have lost something bigger in the future."
Litvinenko's comments emerged after Labour leader Keir Starmer called for Abramovich - who has always refused links to Putin - to be sanctioned.
"We must stand up to Putin and those who prop up his regime," said Starmer.
"Roman Abramovich is the owner of Chelsea Football Club and various other high-value assets in the United Kingdom.
"He’s a person of interest to the Home Office because of his links to the Russian state and his public association with corrupt activity and practices.
"Last week, the Prime Minister said that Abramovich is facing sanctions. He later corrected the record to say that he isn’t. Well, why on Earth isn't he?"
