U.S. President Joe Biden announces actions to continue to hold Russia accountable for its war on Ukraine, from the Roosevelt Room of the White House, Washington, March 8. UPI-Yonhap

Striking harder at Russia's economy, President Joe Biden ordered a ban on Russian oil imports Tuesday in retaliation for Vladimir Putin's onslaught in Ukraine. The major trade action, responding to the pleas of Ukraine's embattled leader, thrust the U.S. out front as Western nations seek to halt Putin's invasion.

Americans will feel pain, too ― at the gas pump ― Biden acknowledged, declaring, ''Defending freedom is going to cost.''

The imports have been a glaring omission in the massive sanctions put in place on Russia over the invasion. Energy exports have kept a steady stream of cash flowing to Russia despite otherwise severe restrictions on its financial sector.

''We will not be part of subsidizing Putin's war,'' Biden said, calling the new action a ''powerful blow'' against Russia's ability to fund the ongoing offensive.

Biden said the U.S. was acting in close consultation with European allies, who are more dependent on Russian energy supplies and who he acknowledged may not be able to join in immediately. The announcement marked the latest Biden attempt at cutting off Russia from much of the global economy and ensuring that the Ukraine invasion is a strategic loss for Putin, even if he manages to seize territory.

''Ukraine will never be a victory for Putin,'' Biden said.

Ukrainian President Volodymyr Zelenskyy in a tweet praised Biden's action: ''Thankful for US and @POTUS personal leadership in striking in the heart of Putin's war machine and banning oil, gas and coal from US market. Encourage other countries and leaders to follow.''

The European Union this week will commit to phasing out its reliance on Russia for energy needs as soon as possible, but filling the void without crippling EU economies will likely take some time. The U.K., which is no longer part of the EU, announced Tuesday that oil and oil products from Russia will be phased out by the end of the year.

Unlike the U.S., which is a major oil and gas producer, Europe relies on imports for 90% of its gas and 97% of its oil products. Russia supplies 40% of Europe's gas and a quarter of its oil. The U.S. does not import Russian natural gas.

A pump jack operates in the Permian Basin oil production area near Wink, Texas, Aug. 22, 2018. Reuters-Yonhap

The issue of oil sanctions has created a conflict for the president between political interests at home and efforts to impose costs on Russia. Though Russian oil makes up only a small part of U.S. imports, Biden has said he was reluctant to ban it, cutting into supplies here and pushing gasoline prices higher.

Inflation is at a 40-year peak, fueled in large part by gas prices, and that could hurt Biden heading into the November midterm elections.

''Putin's war is already hurting American families at the gas pump,'' Biden said, adding, ''I'm going to do everything I can to minimize Putin's price hike here at home.''

Gas prices have been rising for weeks due to the conflict and in anticipation of potential sanctions on the Russian energy sector. The average price for a gallon of gasoline in the U.S. hit a record $4.17 Tuesday, rising by 10 cents in one day, and up 55 cents since last week, according to auto club AAA.

Biden said it was understandable that prices were rising, but cautioned the U.S. energy industry against ''excessive price increases'' and exploiting consumers.

Even before the U.S. ban many Western energy companies including ExxonMobil and BP moved to cut ties with the Russia and limit imports. Shell, which purchased a shipment of Russian oil this weekend, apologized for the move Tuesday amid international criticism and pledged to halt further purchases of Russian energy supplies. Preliminary data from the U.S. Energy Department shows imports of Russian crude dropped to zero in the last week in February.

In 2021, the U.S. imported roughly 245 million barrels of crude oil and petroleum products from Russia ― a one-year increase of 24%, according to the U.S. Energy Information Administration.