Two of Chelsea owner Roman Abramovich's closest allies have today been hit by British sanctions as the Government froze assets estimated to be worth up to £10billion.
The Foreign Office said the action against Eugene Tenenbaum and David Davidovich represented the largest asset freeze in UK history.
The government said the measures would prevent the assets from being repatriated to Russia and used to fund the country's war machine.
Mr Tenenbaum is a director at Chelsea Football Club and is known to be one of Mr Abramovich's closest business associates.
Mr Davidovich has previously been described as Mr Abramovich's 'much lower-profile right-hand man'.
The action against the pair has been co-ordinated with Jersey's freezing of £5.4billion worth of assets related to Mr Abramovich.
The total number of oligarchs, their family members and associates sanctioned by Britain since Russia's invasion of Ukraine began in February now stands at 106.
Corporate filings have shown Mr Tenenbaum took control of Evrington Investments Limited, an Abramovich-linked company, on 24 February.
This immediately followed Russian President Vladimir Putin's launching of his brutal assault on Ukraine.
Mr Davidovich, who has also been hit with a UK travel ban today, took over Evrington Investments from Mr Tenenbaum last month, the Foreign Office said.
Foreign Secretary Liz Truss said: 'We are tightening the ratchet on Putin’s war machine and targeting the circle of people closest to the Kremlin.
'We will keep going with sanctions until Putin fails in Ukraine. Nothing and no one is off the table.'
Mr Abramovich, who is currently trying to sell Chelsea, was himself sanctioned by the Government on 10 March.
He is among several Russian oligarchs to have been hit with punitive measures due to their closeness to Mr Putin's regime.
Police on Jersey, an island some 85 miles south of England, have this week searched premises suspected to be connected to Mr Abramovich and his business activities there.
The 55-year-old billionaire is currently thought to be in Moscow.
He is facing crippling sanctions from a host of other Western countries, including France, who seized his £90million villa on the French Riviera on Tuesday.
Chelsea have been frozen as an asset of Mr Abramovich, although the Premier League club have been granted a special licence to carry on playing matches.
UK Government analysis shows Russia is heading for its deepest recession since the collapse of the Soviet Union.
Around 60% of the country's foreign currency reserves, worth £275billion, are currently frozen.