President Joe Biden has announced stinging new sanctions on Russian oil following Moscow's invasion of Ukraine.
Biden said that the US would ban imports of Russian oil, the latest in a series of economic sanctions against Putin's Russia.
Prior to the announcement, oil rallied on expectations that Biden would stop Russian oil from entering the US.
Meanwhile, the US has said that Russia's invasion of Ukraine has forced 2 million people from their homes, most seeking shelter in neighbouring countries.
The UN refugee agency UNHCR said 2,011,312 people have fled since Russia launched its brutal assault on Ukraine on 24 February, with Poland hosting around 1.3 million Ukrainian refugees.
Most refugees are fleeing Russia's bombardments of packed cities such as Kyiv and Kharkiv, with thousands of civilians believed killed in shelling and rocket fire.
UN refugee chief Filippo Grandi said in a tweet: "Today the outflow of refugees from Ukraine reaches two million people."
Between two to three million people were made homeless during the eight years of civil war in the former Yugoslavia, making Ukraine the fastest-growing refugee crisis in Europe since World War 2.
Russia has threatened to cut gas supplies to Europe if oil exports from the country are banned, in the latest escalation in the Ukraine crisis.
Russia's Deputy Prime Minister Alexander Novak said that any attempt to block Ukrainian oil could lead to prices skyrocketing to $300 a barrel and warned it could lead to Moscow cutting gas to Germany.
"We have every right to take a matching decision and impose an embargo on gas pumping through the [existing] Nord Stream 1 gas pipeline," he warned.
Around 40 percent of the EU's gas and 30 percent of its oil supplies come from Russia, according to the BBC.