The US and UK are poised to ban Russian oil and the EU is sharply reducing gas imports as countries harden their response to the invasion of Ukraine.
Both the US and British governments are likely to make their announcements later on Tuesday.
The European Commission has just announced it will reduce demand for Russian gas by two-thirds – the EU gets 40% of its gas from Russia.
The measures are meant to hurt Russia, with its economy dependent on energy.
But such action could also send prices soaring. Investor fears of an embargo drove Brent crude oil to $139 (£106) a barrel at one point on Monday – its highest level for almost 14 years.
Russia earlier warned it may close its main gas pipeline to Germany if the West bans Russian oil.
US President Joe Biden is expected to make the announcement at 10:45 local time (15:45 GMT), US media reports. The White House has not confirmed the ban on oil, but said the president would be announcing further actions against Russia.
The move has political support. On Monday senior Republicans and Democrats in Congress announced a bipartisan agreement to suspend normal trade relations with Russia and Belarus.
“Taking these actions will send a clear message to Putin that his war in unacceptable and the United States stands firmly with our Nato allies,” they said. “We are committed to using the tools at our disposal to stop Russia’s unconscionable and unjust war.”
About 8% of US oil and refined product imports come from Russia.
