Updated 5.55pm -
he United States and Britain announced Tuesday they are cutting off imports of Russian oil, in the most far-reaching action yet by Western allies to punish Moscow for invading Ukraine.
President Joe Biden announced the US embargo, part of a broader prohibition including Russian natural gas and coal, with US Democrats threatening legislation to force his hand, despite the likely impact on already soaring gas prices.
"Russian oil will no longer be acceptable at US ports and the American people will deal another powerful blow to (President Vladimir) Putin's war machine," Biden said, adding that the decision was taken "in close consultation" with allies.
"Ukraine will never be a victory for Putin," Biden vowed from the White House, minutes after Britain announced that Europe's second-largest economy would phase out Russian oil imports by the end of the year.
"Putin may be able to take a city, but he will never be able to hold the country."
The US ban has support from both parties in Washington, although economists have been divided on the effect of turning off the spigot, with oil prices already soaring above $120 a barrel.
Brent crude, the international benchmark, rose by more than five percent on Tuesday on news of Biden's imminent announcement.
Russia accounts for eight percent of US imports of oil and petroleum products.
The White House will have to reassure voters already alarmed over spiraling gasoline prices, which are threatening Democrats' chances of holding on to Congress in November's midterm elections.
Americans are now paying an average of $4.17 per gallon, a 72 cent increase in just one month and the highest price at the pump since the global economic downturn of 2008.
EU to 'vastly reduce' oil, gas imports from Russia this year
Earlier on Tuesday, the European Union said it wants to vastly reduce Russian gas imports this year.
The European Commission said it could erase a huge share of its dependency on Russia by tapping new gas supplies, ramping up reserves for next winter and accelerating efforts to be more energy efficient.
"By the end of this year, we can replace 100 billion cubic metres of gas imports from Russia. That is two-thirds of what we import from them," EU Commission vice president Frans Timmermans told reporters in Strasbourg, France.
"This will end our over-dependency and give us much-needed room to manoeuvre," added Timmermans, who leads EU policy-making on energy and climate change.
Russia supplies 40 per cent of the EU's gas needs, with Italy, Germany and several central European countries especially dependent. A quarter of its oil supply also comes from Russia.