Progressive Democratic lawmakers urged U.S. President Joe Biden on Monday to shift the U.S. approach to the war in Ukraine by directly negotiating with Russia.

A letter signed by 30 House Democrats in the Congressional Progressive Caucus, led by Representative Pramila Jayapal, said they appreciated Biden’s commitment “to Ukraine’s legitimate struggle against Russia’s war of aggression” and acknowledged U.S. economic, military and humanitarian aid has been critical to Ukraine’s success in fighting off Russia.

But the lawmakers said, in the letter first reported by the Washington Post, that diplomatic efforts should also be a part of the U.S. approach to ending the war that has had a catastrophic toll on the Ukrainian people as well as threatening global food and poverty crises through rising fuel and grain costs.

“As legislators responsible for the expenditure of tens of billions of U.S. taxpayer dollars in military assistance in the conflict, we believe such involvement in this war also creates a responsibility for the United States to seriously explore all possible avenues, including direct engagement with Russia, to reduce harm and support Ukraine in achieving a peaceful settlement,” the lawmakers wrote.

In a June 2022 press conference, Biden acknowledged that possibility when asked if Ukraine would have to cede territory to Russia to put an end to the conflict.

“It appears to me that, at some point along the line, there’s going to have to be a negotiated settlement here. And what that entails, I don’t know. I don’t think anybody knows at the time,” Biden told reporters.

The lawmakers specified it was not the place of the U.S. to pressure Ukraine into accepting a settlement, writing that any “framework would presumably include incentives to end hostilities, including some form of sanctions relief, and bring together the international community to establish security guarantees for a free and independent Ukraine that are acceptable for all parties, particularly Ukrainians.”

The U.S. has sent nearly $60 billion in humanitarian, economic and military aid to Ukraine since Russia’s unprovoked invasion in February. In the Monday letter, members of the Congressional Progressive Caucus said they are still in favor of continued aid.

But House Minority Leader Kevin McCarthy — who is poised to become Speaker of the House if Republicans win control of the U.S. House of Representatives in the November midterm elections — said continuing U.S. aid to Ukraine is not assured, given domestic economic concerns.

“I think people are going to be sitting in a recession, and they’re not going to write a blank check to Ukraine,” McCarthy told U.S. political news outlet Punchbowl News last week.

Not all Republican leaders agree. Senate Minority Leader Mitch McConnell called for more U.S. aid to Ukraine in a statement last Friday, saying “The Biden Administration and our allies need to do more to supply the tools Ukraine needs to thwart Russian aggression. It is obvious this must include additional air defenses, long-range fires, and humanitarian and economic support to help this war-torn country endure the coming winter.”

Progressive Democrats did praise Biden’s approach, saying the administration’s policy was critical in preventing an all-out nuclear conflict.

“We are under no illusions regarding the difficulties involved in engaging Russia given its outrageous and illegal invasion of Ukraine and its decision to make additional illegal annexations of Ukrainian territory. However, if there is a way to end the war while preserving a free and independent Ukraine, it is America’s responsibility to pursue every diplomatic avenue,” the letter said.