Britain today moved to cripple Russian banks’ access to the UK's financial institutions and curtail oligarchs' luxury lifestyles in the capital.
Over 100 people, including five Russian "elite individuals" with close links to the Kremlin, are facing immediate sanctions.
The wealthy tycoons - major players in Moscow - are being targeted in response to Russia's invasion of Ukraine.
The UK instantly froze assets worth £154bn in VTB, the second largest bank in Russia, while Rostec, the county's biggest defence company with over two million employees, will also face reprisals.
They were announced as part of measures Prime Minister Boris Johnson said were designed to stunt Russia's economy.
Russia's youngest billionaire, who was once married to Putin's daughter, and the chairman of a bank with links to the Salisbury Novichok poisoning are facing sanctions.
The son of the President's long-serving spy chief will also be punished.
Restrictions will be placed on five named individuals - Denis Bortnikov, Kirill Shamalov, Petr Fradkov, Yuri Slyusar and Elena Aleksandrovna Georgieva.
They cannot travel to the UK or interact with British businesses.
The five will all be targeted by PM's 'largest and most severe' sanctions against Russia.
Mr Johnson told MPs “this hideous and barbarous venture of Vladimir Putin must end in failure” as he revealed London will now target all major Russian banks.
Here's all we know about Putin's cronies now facing up to strict UK sanctions.
Petr Fradkov
The 43-year-old was educated in London but now he will not be allowed to the country where he grew up.
He is the chairman and CEO of Promsvyazbank (PSB) bank and is also the general director of the Russian Export Center.
Petr Fradkov is the son of Mikhail Fradkov, a former prime minister of Russia.
Earlier this week he was subjected to US sanctions by the American Treasury.
Kirill Shamalov
The mega rich 39-year-old is Russia's youngest billionaire and is the President's former son-in-law.
He was married to Putin's daughter Katerina Tikhonova for five years from 2013 to 2018.
Within 18 months of their wedding, he had acquired a large chunk of shares in a major Russian oil and petrochemical processor called Sibur.
Shamalov was the former economic advisor to the Russian government.
Elena Aleksandrovna Georgieva
Boris Johnson's plan to hit Russia hard and where it really hurts started with this high-profile CEO.
Elena Aleksandrovna Georgieva is the boss of Novikombank, a state-owned defence conglomerate.
Born in Moscow in 1977, she is credited with the company's climb.
JSC Novikombank was established in 1993.
Yuri Slyusar
The UK placed the president of Russia’s United Aircraft Corp and its former deputy trade minister very near the top of the sanction list.
Yuri Slyusar began producing helicopters 10 years ago and his recent rise has caught the eye of many in Moscow.
He graduated from the Lomonosov Moscow State University with a degree in law.
Now his company is one of the major defence organisations which is also being sanctioned as an organisation.
Denis Bortnikov
Denis Bortnikov is the d eputy president of financial institution VTB Bank.
His father, Aleksandr Bortnikov, is the director of Russia's intelligence service, the FSB.
The Foreign Office said: "Bortnikov is the son of Alexander Bortnikov, the head of the Federal Security Service (FSB) which was responsible for the poisoning of political activist Alexey Navalny in August 2020 with a banned chemical agent from the Novichok group."
Aleksandr Bortnikov is said to be one of Putin's most trusted henchmen.