Biden says Republicans are being ‘reckless’ over the debt limit increase.

President Biden urged congressional leaders to raise the debt ceiling on Monday, excoriating Republicans for what he said was “reckless” and “disgraceful” obstruction ahead of a default deadline later this month that he warned would amount to “a self-inflicted wound that takes our economy over a cliff.”

Mr. Biden, trying to convey the risks to everyday Americans, warned that they could see the effects as early as this week if Senate Democrats were not able to vote to raise the debt ceiling. The debt ceiling controls the amount of money the government can borrow to fulfill its financial obligations, including Social Security checks, salaries for military personnel and other bills.

“It starts with a simple truth: The United States is a nation that pays its bills and always has,” Mr. Biden said. “If we’re going to make good on what has already been approved by previous Congresses, and previous presidents and parties, we have to pay for it.”

The remarks presaged increased public engagement by Mr. Biden on an issue that risks economic crisis.

Mr. Biden pointed out that Republicans had voted several times to increase the debt limit under President Donald J. Trump but are threatening to filibuster any attempt by Democrats to raise it this time. He said that he would not be expecting Republicans to “do their part,” but he warned them “not to use procedural tricks to block us from doing the job.”

Technically, the United States hit its debt limit at the end of July, following a two-year extension that Congress agreed to in 2019. Treasury Secretary Janet L. Yellen has been using “extraordinary measures” since then to delay a default. Those are essentially fiscal accounting tools that curb certain government investments so that the bills can continue to be paid.

Ms. Yellen warned Congress last week of “catastrophic” consequences should lawmakers fail to suspend or raise the statutory debt limit before Oct. 18, which the Treasury believes is the date the United States will run out of enough money to pay all its bills.

Congress raises the debt limit to cover spending it has already approved, and the Treasury has warned that failure to do so would tank financial markets and have wide-ranging impact on Americans: Defaulting could pause Social Security checks, delay the pay of military troops, and interfere with child tax credit payments.

But Republicans — who had voted to raise the debt cap by trillions when their party controlled Washington — have moved to block a spending bill needed to avoid default. Instead, Republicans including Senator Mitch McConnell of Kentucky, the minority leader, have sought to place political responsibility on Democrats, who are at the same time seeking to advance a sprawling social policy bill that could cost as much as $3.5 trillion.

“Bipartisanship is not a light switch that Speaker Pelosi and Leader Schumer may flip on to borrow money and flip off to spend it,” Mr. McConnell wrote in a letter to Mr. Biden on Monday, referring to Senator Chuck Schumber of New York, the majority leader. “For two and a half months, we have simply warned that since your party wishes to govern alone, it must handle the debt limit alone as well.”

The president said he planned on talking to Mr. McConnell about the letter: “He and I have been down this road once before,” Mr. Biden said.

Democrats have so far refused to try and raise the debt ceiling through a fast-track process known as reconciliation. On Monday, Mr. Schumer told Democrats that a spending bill needed to reach Mr. Biden’s desk within days, not weeks.

“Let me be clear about the task ahead of us: We must get a bill to the President’s desk dealing with the debt limit by the end of the week. Period. We do not have the luxury of waiting until Oct. 18,” he wrote in a “dear colleague” letter dated Monday.

Asked if he supported reconciliation to raise the debt ceiling, Mr. Biden said the process would be “fraught with all kinds of potential danger or miscalculation,” and said the way to proceed would be a vote on a bill to raise the limit.

Administration officials say Mr. Biden will continue to pressure Republicans to step aside — by breaking their filibuster — and allow Democrats to vote on their own this week to raise the limit.

“Let us vote,” Mr. Biden said. “and end the mess.”

As he urges congressional leaders to find a way forward on raising the debt limit, Mr. Biden still must drum up support for a bipartisan infrastructure deal and an expansive social spending plan.

“I’ve been able to close the deal on 99 percent of my party,” Mr. Biden said, before adding that “two people” remain opposed to the second piece, a reference to Senator Joe Manchin III of West Virginia and Senator Kyrsten Sinema of Arizona.

“It’s not a smart thing to negotiate with yourself in public,” Mr. Biden said, when asked if he would support a lower figure on the reconciliation package.