The US has announced sanctions on Russian President Vladimir Putin's daughters, Foreign Minister Sergei Lavrov and major banks, among others.
The measures follow new revelations of atrocities by Russian troops in Ukraine, including images of bodies of civilians scattered on the streets of Bucha, near the capital Kyiv, the BBC reported.
Russia says, without evidence, the images are staged by Kyiv officials.
Even though satellite images have shown the civilians were killed when Russians were in control of Bucha, Putin on Wednesday described the event as a "crude and cynical provocation by the Kyiv regime".
Referring to the Bucha murders, US President Joe Biden said on Wednesday: "There's nothing less happening than major war crimes."
"Responsible nations have to come together to hold these perpetrators accountable," Mr Biden added.
The US said that Mr Putin's daughters, Katerina Vladimirovna Tikhonova and Maria Vladimirovna Vorontsova, were being put under sanctions "for being the adult children of Putin, a person whose property and interests in property are blocked".
The US sanctions announced by the White House include economic measures to ban new investment in Russia severe financial sanctions on Russia's largest private bank, Alfa Bank, and its largest financial institution, Sberbank, sanctions on critical major state-owned enterprises and sanctions on Russian government officials and their family members.
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Meanwhile, the UK has announced further sanctions against eight oligarchs and Russian banks, including the country's largest, Sberbank, and Credit Bank of Moscow.
The European Union is also debating cutting off Russian coal imports as concern over alleged war crimes increases.
Before the new raft of sanctions was announced in Washington, Ukrainian President Volodymyr Zelenskyy said he could not "tolerate any indecisiveness".