Sen. Joe Manchin, D-W.Va., accused progressive Democrats of holding the bipartisan infrastructure bill “hostage” in a scathing statement on Monday, adding that he would not support the broad spending bill they favor without a thorough review of how its policies would impact the U.S. economy.

Manchin’s reluctance represents a major obstacle for Democratic leaders, who are pushing to pass both bills by as soon as this week. The West Virginia senator has yet to formally endorse the spending bill, which outlines $1.75 trillion in costs over a 10-year period.

“Simply put, I will not support a bill that is this consequential without thoroughly understanding the impact it will have on our national debt, our economy and the American people,” Manchin said. “Every elected representative needs to know what they are voting for and the impact it has, not only on their constituents, but the entire country.”

“I, for one, also won’t support a multitrillion-dollar bill without greater clarity about why Congress chooses to ignore the serious effects inflation and debt have on our economy and existing government programs,” he added.

Manchin’s remarks followed the House Progressive Caucus’ declaration last week that it would not vote to approve the bipartisan bill focused on physical infrastructure projects unless it is brought up at the same time as a finalized social spending bill. Progressives have also demanded that Manchin and fellow moderate holdout Sen. Kyrsten Sinema publicly endorse the bill.

A framework agreement for President Biden’s “Build Back Better Act” includes more than $500 billion in climate-related spending and changes to the tax code targeting the wealthiest Americans. But the agreement also cut or eliminated some programs favored by progressives after pushback from Manchin and others.

Manchin expressed frustration with his progressive colleagues, accusing them of playing “political games” to hold back consideration of the bipartisan infrastructure bill.

“As I have said before, holding this bill hostage won’t work to get my support for the reconciliation bill,” Manchin said. “I’m open to supporting a final bill that helps move our country forward, but I am equally open to voting against a bill that hurts our country and the American people.”