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President Joe Biden on Tuesday announced that he is suspending a federal rule preventing the sale of higher biofuel-blended petrol this summer as his administration seeks to clamp down on increasing prices at the pump.
Delivering remarks at a biofuel company in Menlo, Iowa, Mr Biden blamed Russia's invasion on Ukraine for the increase in petrol prices and for the acceleration of US inflation last month.
"Seventy percent of the increase in prices in March came from [Russian President Vladimir] Putin's price hike in gasoline," he said.
Mr Biden said American families' budgets should not "hinge on whether a dictator declares war and commits genocide half a world away".
Government data on Tuesday showed consumer prices rose by 8.5 per cent in March from 12 months earlier, the largest year-on-year gain since 1981.
"I'm committed to do whatever I can to help, even if it's an extra buck or two in the pockets where they fill up will make a difference in people's lives," Mr Biden said.
Most petrol sold in the US is blended with 10 per cent ethanol. The Environmental Protection Agency will issue an emergency waiver to allow Americans to buy E15, a fuel that is made up of 15 per cent ethanol blend, from June 1 to September 15.
The move comes as the president faces growing pressure over inflationary concerns. The consumer price index surged 1.2 per cent for the month of March, the US Labour Department reported on Tuesday. Fuel was the primary driver for inflation last month, with average petrol prices hitting a record-high of $4.33 per gallon.
Administration officials said the EPA had begun to analyse the “emergency” step of allowing more E15 gasoline sales for the summer and determined it was not likely to have significant on-the-ground air quality impacts. That is despite some environmentalists long arguing that more ethanol in petrol increases pollution.
The waiver is another effort to help ease global energy markets that have been rocked since Russia invaded Ukraine. Last month, the president announced the US would release 1 million barrels of oil per day from the nation’s strategic petroleum reserve over the next six months.
Members of both parties in Congress have called on Mr Biden to grant the E15 waiver.
“I know Iowa biofuel producers can ramp up production and provide affordable, low-carbon biofuels to the country if the president allows summer sales of E15,” Chuck Grassley, Republican senator from Iowa, said.
Mr Biden's visit to Iowa comes amid slumping approval ratings and questions over his response on the war in Ukraine, inflation and the supply chain.
The president's low approval ratings put Democrats in danger of losing at least one chamber of Congress during the midterms later this year, which would deliver a critical setback to his agenda.
Iowa is one of two stops on Mr Biden's travel itinerary this week, during the Senate and House's Easter break. On Thursday the president will travel to Greensboro, North Carolina, to speak on the nation's supply chain challenges.
Agencies contributed to this report