A bipartisan infrastructure deal teeters just a day after it was announced.

Politics|A bipartisan infrastructure deal teeters just a day after it was announced.

• June 25, 2021, 7:09 p.m. ET

A bipartisan infrastructure deal appeared imperiled on Friday as Republicans vented over President Biden’s comment that he would not sign the agreement for $579 billion in new infrastructure spending without a second, far more ambitious package on hand.

Mr. Biden and top Democrats have long been adamant that they will accept a narrower public works bill only with a commitment to move forward on another bill, using the fast-track budget reconciliation process, that includes home-based health care, extensive climate provisions, paid leave and other liberal priorities paid for by tax increases on wealthy corporations and individuals.

On Thursday, as Mr. Biden was celebrating the deal with 10 centrist senators over the $1.2 trillion overall infrastructure package, he declared to reporters, “If this is the only thing that comes to me, I’m not signing it.”

“It’s in tandem,” he added.

And while Republicans have acknowledged the inevitability of Democrats passing additional legislation on their own, the implication that Mr. Biden would not sign the bipartisan accord until Congress passed a reconciliation bill rankled Republicans.

“I don’t think that’s going to pass, and I think they killed any opportunity,” Representative Kevin McCarthy of California, the minority leader, said at his weekly news conference. “I think it was disingenuous in every shape or form.”

The senators who helped negotiate the compromise convened a private call Friday afternoon to express frustration with Mr. Biden’s comments and concern that they had upended what had been seen as good-faith negotiations. The call, first reported by The Washington Post, was described by two people familiar with it on the condition of anonymity.

“No deal by extortion!” Senator Lindsey Graham, Republican of South Carolina, said on Twitter after having endorsed an initial framework this month. “It was never suggested to me during these negotiations that President Biden was holding hostage the bipartisan infrastructure proposal unless a liberal reconciliation package was also passed.”

Mr. Biden spoke with Senator Kyrsten Sinema, Democrat of Arizona and a leader in the negotiations, on Friday to reiterate his support for both the bipartisan plan and a second package. He told Ms. Sinema the bills were priorities “he wants to see advance through the legislative process as quickly as possible, pass as quickly as possible and be presented to him for signing as quickly as possible,” according to a readout provided by the White House.

“People are very committed to what we’ve done,” said Senator Jeanne Shaheen, Democrat of New Hampshire and one of the negotiators. “I didn’t understand the president to take that position, so I’m going to continue to operate and try and build support for the infrastructure package.”

Legislative text for the bipartisan deal still needs to be written as Democrats also work on the second, potentially multitrillion-dollar package, a priority for liberal lawmakers. But that second package, expected to be passed using the reconciliation process, may not be ready for votes until the fall, given the strict budgetary hurdles it must clear.

“There’s no question there’s work ahead, and he’s ready to roll up his sleeves and work like hell to get it done,” Jen Psaki, the White House press secretary, said at a briefing on Friday.

Lawmakers say the bipartisan deal, which would allocate $579 billion in new federal funds for roads, bridges, broadband and other public works projects, would be the largest single infrastructure investment in modern American history.

Ms. Psaki said it was up to Republicans to decide if they would vote against the bill “simply because they don’t like the mechanics of the process.”

“That’s a pretty absurd argument for them to make,” she added. “Good luck on the political front on that argument.”