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The US has announced a new wave of sanctions on Russian banks and elites that President Joe Biden said will impart lasting damage on its economy.
Mr Biden said on Wednesday that "Russia has already failed in its initial war" after its forces were turned back from the Ukrainian capital of Kyiv, but warned "this fight is far from over".
The US acted against Sbrebank and Alfa Bank, Russia's two largest public and private banks, by prohibiting access from funds going through the US financial system and barring Americans from doing business with those banks.
"There's nothing less happening than major war crimes," Mr Biden said in a speech, referring to the Ukrainian town of Bucha retaken from Russian forces, where bodies of civilians shot to death had been found.
"Responsible nations have to come together to hold these perpetrators accountable," he said. "And together with our allies and our partners, we're going to keep raising economic costs and ratchet up the pain for [Russian President Vladimir] Putin."
He earlier said US and western sanctions would "stifle Russia’s ability to grow for years to come".
Mariya Putina and Katerina Tikhonova, Russian President Putin's two adult daughters, were also targeted in sanctions that extend to Russian Foreign Minister Sergei Lavrov's wife and daughter, and members of Russia's security council, the White House said.
The US believes Mr Putin hides his wealth with family members and that the penalties will cut them off from the US financial system and freeze assets they hold in the country.
Mr Biden was expected to sign an executive order later on Wednesday that also prohibits any American person or entity from investing in Russia.
Meanwhile, the UK ratcheted its sanctions against the Russian regime, freezing the assets of two banks and adding a further eight oligarchs to its list of targeted people. Foreign Secretary Liz Truss also said she will urge G7 colleagues to maintain the momentum with further waves of sanctions when they meet on Thursday. European diplomats have also been meeting with the intention of agreeing new measures.
Ms Truss said: "Our latest wave of measures will bring an end to the UK's imports of Russian energy and sanction yet more individuals and businesses, decimating Putin’s war machine.
"Together with our allies, we are showing the Russian elite that they cannot wash their hands of the atrocities committed on Putin's orders. We will not rest until Ukraine prevails."
The latest moves are "dramatically escalating" the financial shock on Russia that could send the country back to the Soviet-style living standards in the 1980s.
The US Justice Department also announced new enforcement actions against Russian criminal activity.
Attorney General Merrick Garland said the department has charged oligarch Konstantin Malofeyev with sanctions violations, saying he provided financing for Russian separatism in Crimea. The criminal charges are the first brought against a Russian oligarch since the February 24 invasion.
"It does not matter how far you sail your yacht. It does not matter how well you conceal your assets. It does not matter how cleverly you write your malware or hide your online activity. The Justice Department will use every available tool find you your plots and hold you accountable," Mr Garland said during a briefing.
Grim images emerging from the Ukrainian city of Bucha include a mass grave and bodies of people shot at close range, prompting calls for tougher action against Moscow and an international investigation.
The White House said it will continue to impose penalties on Russia for its actions in Ukraine, including Bucha.
US Secretary of State Antony Blinken said the killings were part of a deliberate Russian campaign to commit atrocities. Russia denies targeting civilians and said images of the corpses were a “monstrous forgery” staged by the West. Neither provided evidence to support the assertions.
A senior French official said the European Union would also probably impose new sanctions on Wednesday. Two European diplomats said the final package of sanctions would be announced in a co-ordinated fashion.
Agencies contributed to this report