Washington DC - Seven US senators from both parties issued a statement Sunday questioning the legality of President Donald Trump's deal to allow Russian diesel exports despite a ban in place since Moscow's invasion of Ukraine.

"Congress explicitly banned Russian energy imports in 2022 to prevent American dollars from financing Putin's brutal war against Ukraine," the joint statement from the senators began.

"Congress was clear: the US should not import oil from Russia until it ends its aggression against Ukraine and ceases threats against our NATO Allies."

The statement was co-signed by Democratic Senators Jeanne Shaheen, Richard Blumenthal, and Ron Wyden, along with Republican Senators Susan Collins, Lisa Murkowski, John Curtis, and Thom Tillis.

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It comes after Trump announced on Friday an agreement with Russian leader Vladimir Putin to release a massive quantity of diesel in exchange for temporarily easing US sanctions.

"President Trump's decision to allow Russian diesel imports to the US runs directly counter to that law. The Administration has also failed to consult with Congress or submit any explanation to justify its decision as required by statute," the statement added.

The senators also condemned the decision to "provide Putin with a financial lifeline while Russia continues to kill Ukrainian civilians," and urged the Trump administration to "immediately reverse course."

Treasury Secretary Scott Bessent defended the deal Sunday, telling Fox News in an interview, "We are going to do it with all the legal authorities we have."