Second District U.S. Rep. Jared Golden and eight other centrist House Democrats say they will support the advance of a $3.5 trillion social policy spending and budget plan only after the House passes a $1 trillion bipartisan infrastructure bill approved by the Senate on Tuesday.

The announcement, conveyed in a letter Thursday to House Speaker Nancy Pelosi, D-Calif., throws a wrench into her strategy to pass both measures with a narrow, three-vote majority in the chamber. Progressive Democrats have the opposite demand: that the House pass the budget bill – which contains many of President Biden’s top priorities – before they will vote for the infrastructure legislation, so as to increase leverage on moderate House Democrats to also support its passage.

In the letter, Golden and his colleagues rejected the progressives’ plan, which would likely delay passage of the infrastructure bill for months.

“With the livelihoods of hardworking American families at stake, we simply can’t afford months of unnecessary delays and risk squandering this once-in-a-century, bipartisan infrastructure package,” they wrote. “It’s time to get shovels in the ground and people to work.”

Golden, who has bucked his caucus in a number of high-profile votes and has not revealed his position on the social policy budget bill, said in a written statement that he found the delay on infrastructure unacceptable.

“We know from experience over the last year that it can take many months or longer for the federal government to stand up for new programs and deliver new resources,” Golden wrote. “We can’t afford to wait until October or later to pass this infrastructure bill, and I won’t consider voting for a budget resolution until we do.

“This bipartisan bill was good enough to get votes from both Bernie Sanders and Mitch McConnell, and it is a disservice to the American people to hold it hostage for political games,” he added.

The games he referred to are likely the high-stakes balancing act by Pelosi and Biden to pass both bills with the narrowest of majorities in both chambers – the infrastructure bill on a bipartisan basis via regular order, and the budget bill via the reconciliation process, which avoids a likely Republican filibuster in the Senate.

Progressive Democrats in the House fear their moderate colleagues could vote against the $3.5 trillion social policy and budget package if the infrastructure package they want has already passed. The 96-member progressive House caucus has therefore said the social policy package must pass first.

The other signatories to the letter, which became public early Friday morning, were Reps. Josh Gottheimer of New Jersey; Georgia’s Carolyn Bourdeaux and Filemon Vela; Henry Cuellar and Vicente Gonzalez of Texas; Hawaii’s Ed Case, Jim Costa of California and Kurt Schrader of Oregon.

First District Rep. Chellie Pingree, a member of the Democrat’s progressive caucus, declined to comment on the developments.

The infrastructure bill passed the Senate 69-30 Tuesday, with Senate Minority Leader Mitch McConnell in support. It would be the largest federal infusion of infrastructure spending in a decade, with $550 billion in new spending on roads, bridges, rail, high-speed internet access and other projects.

The social policy budget bill would represent the most significant expansion of the nation’s safety net since the mid-1960s, expanding Medicare to include hearing, vision and dental benefits, and making preschool and two years of community college tuition free, while making investments to fight climate change and lower prescription drug prices. It would be paid for through increased taxes on corporations, the wealthy and large inheritances.

Golden, who in 2018 became the first person in 102 years to unseat an incumbent representing Maine’s 2nd District, has broken with his colleagues on some their top priorities even as he champions other progressive causes. He opposed the $1.9 trillion COVID-19 relief bill that became law in March, as well as police reform and legislation to close gun background check loopholes. He argued the relief bill was wastefully targeted and far bigger than was needed at the time, as hundreds of millions of dollars from previous relief packages remained in the pipeline and unspent.