The United States faces a default between December 21 and January 28 if Congress does not act to raise or suspend the debt ceiling, a Washington think tank warned Friday.

The think tank’s screening, the Bipartisan Policy Center, was a narrower window than that provided last month, and the non-partisan group suggested that the actual deadline, or date X, may be towards the earlier end. from this beach.

Democrats and Republicans seem to have tempered their tone about raising the debt ceiling this time around. While lawmakers have yet to make a decision to raise the borrowing limit, they are exploring a range of ways to raise it, including some that could ultimately empower the White House to avoid the kind of dead ends that have regularly crippled Washington.

Republicans continue to publicly insist that Democrats must act on their own to solve the problem, while Democrats countered that raising the borrowing limit is a shared responsibility given that both political parties have contracted big debts in recent years.

“Those who think the debt limit can be safely pushed behind the December legislative pile-up are misinformed,” said Shai Akabas, director of economic policy at the Bipartisan Policy Center. “Congress would be flirting with financial disaster if it left for the holidays without addressing the debt limit.”

Treasury Secretary Janet L. Yellen warned lawmakers in November that the United States may be unable to pay its bills soon after December 15. In testimony before the Senate Banking Committee this week, she underscored the urgency of the matter.

“I cannot stress enough that it is essential that Congress address this issue,” Ms. Yellen said. “America needs to pay its bills on time and in full. If we don’t, we’ll gut our current recovery. “

In September, Ms Yellen called for the elimination of the debt limit, explaining that it had become a destructive policy that posed unnecessary risks to the economy. After approaching the first default in U.S. history, Congress in October raised the legal debt limit to $ 480 billion, an amount the Treasury Department said would allow the government to continue borrowing until ‘in early December.

Congressional leaders quietly discussed ways to address the debt ceiling, after Republicans warned they would not help Democrats cross the 60-vote threshold needed to break a Republican obstruction against legislation aimed at increase the borrowing limit.

Senators Chuck Schumer of New York, the majority leader, and Mitch McConnell of Kentucky, the minority leader, have spoken on several occasions in recent weeks about the issue, but have remained silent in public on a possible solution.

The debate was further complicated by former President Donald J. Trump and his continued influence on the Republican Party. He has repeatedly criticized Mr. McConnell and other Republican senators for supporting a procedural vote in October that allowed Democrats to raise the debt ceiling.

But Mr McConnell, while pushing Democrats to raise the borrowing ceiling without help from his conference, promised this week that a default would be avoided.

Credit…Al Drago for the New York Times

“Let me assure everyone that the government will not default as it never has,” McConnell said Tuesday. Pressed further, he added: “We have some useful discussions on the way forward. “

Cut off from both the $ 1.9 trillion coronavirus relief plan passed in March and the $ 2.2 trillion climate, tax and spending plan Democrats are trying to push through the Senate, Republicans have refused to help Democrats meet the debt incurred by both parties. They took this position even though the leaders of both parties approved the spending that contributed to the rising debt.

Democrats, in turn, balked at a Republican demand to use a fast-track process known as budget reconciliation to raise the debt limit without Republican votes. Democrats used the process to pass the coronavirus relief plan and they are using it again for the climate, fiscal and spending plan, but argued Republicans should help prevent the government from defaulting.

Aides on both sides, while warning that a solution has not been agreed upon, noted that party leaders have so far refrained from publicly blaming the issue.

To get around the deadlock, some officials have raised the possibility of giving the administration the power to raise the debt ceiling, while still giving Congress the ability to disapprove the decision by simple majority.

Some lawmakers, however, may be unwilling to cede that power to the White House or lose a club often used by the minority party to lobby, especially when 60 votes are needed to end an obstruction in the Senate.

Other officials have proposed to tie legislation raising the debt limit to the comprehensive annual defense policy bill, which is the last major piece of legislation to pass that lawmakers plan to approve in December.

But it’s not clear whether such a plan would be successful: setting a debt ceiling increase could jeopardize the Republican votes needed to counter the bloc of Liberal Democrats who typically oppose the Defense Bill for protest against military spending. Representative Kevin McCarthy, California Republican and minority leader, warned on Friday that such a move could derail the passage of the entire package.

The Bipartisan Policy Center said there was additional uncertainty about the debt limit this year due to the pandemic and the various economic aid programs that are still ongoing.

December 15 is a particularly important date as the Treasury Department is due to make a payment of $ 118 billion to the Highway Trust Fund. If corporate tax receipts owed on that day are low, the Treasury could face a liquidity shortage and the United States may be unable to meet all of its obligations, such as paying social security and funding social security. military paychecks.

The Congressional Budget Office said this week that it expects the Treasury to run out of cash by the end of December if Congress does not act. The budget office has suggested, however, that the Treasury may defer some payments from the Highway Trust Fund mandated by the recently passed infrastructure law, potentially avoiding a default until January.

Along with its updated projection, the Bipartisan Policy Center unveiled a new proposal for dealing with the debt limit, though it is unlikely to help lawmakers this time around.

Proposal, which is introduced by Rep. Jodey C. Arrington, Republican of Texas, and Scott Peters, Democrat of California, would establish a process giving the president the power to suspend the debt ceiling in the next fiscal year as long as Congress does will not adopt a resolution. block movement within 30 days. The president would then have to bring a debt reduction proposal to Congress for separate consideration.