A special congressional committee created to try to curb the national debt abandoned its work and conceded failure Monday, the latest setback in a long effort by Washington to overcome ideological differences and stem the rising tide of red ink.

In a joint statement issued hours before a midnight deadline, the Democratic and Republican leaders of the panel said that they were “deeply disappointed” by their inability to reach an agreement and that they hope for progress in the months ahead.

“Despite our inability to bridge the committee’s significant differences, we end this process united in our belief that the nation’s fiscal crisis must be addressed and that we cannot leave it for the next generation to solve,” said the statement from Rep. Jeb Hensarling (R-Tex.) and Sen. Patty Murray (D-Wash.). “We remain hopeful that Congress can build on this committee’s work and can find a way to tackle this issue in a way that works for the American people and our economy.”

The collapse of the “supercommittee” offered fresh evidence of partisan gridlock and legislative dysfunction as policymakers gird for the 2012 elections with the White House and Congress up for grabs.

The breakdown left the nation facing the prospect of automatic reductions to government agency budgets in January 2013 — an outcome that both parties agree could damage the military and government services such as law enforcement, food inspection and transportation safety.

Some GOP lawmakers immediately issued statements vowing to stop the Pentagon cuts. But President Obama sought to block that effort, threatening Monday to veto any legislation aimed at softening the impact of the cuts unless Congress approves a broader debt-reduction plan. Obama urged lawmakers to revisit that task as soon as they return from the Thanksgiving break.

“Already, some in Congress are trying to undo these automatic spending cuts. My message to them is simple: No,” the president said in a televised statement that marked his reentry into the debt debate after weeks of keeping his distance as Congress flailed.

“There will be no easy off-ramps on this one. We need to keep the pressure up to compromise, not turn off the pressure,” he said. “The only way these spending cuts will not take place is if Congress gets back to work and agrees on a balanced plan to reduce the deficit by at least $1.2 trillion. . . . They’ve still got a year to figure it out.”

Congressional leaders in both parties pledged to press on. But in statements issued Monday, they spent more time blaming one another for the political paralysis that has nearly shut down the government twice this year and that in August pushed the U.S. Treasury to the brink of defaulting on the national debt. Although the supercommittee’s failure will not result in an immediate calamity, analysts said it probably will further erode public confidence in Washington — particularly in Congress, which already is held in historically low regard.

At a scathing news conference, New York Mayor Michael R. Bloomberg (I) blamed Obama and lawmakers in both parties for the stalemate, calling the supercommittee collapse a “damning indictment of Washington’s inability to govern this country.”

Sen. Olympia J. Snowe (Maine), a moderate Republican, called the panel “a monumental waste of time and opportunity” that “represents yet another regrettable milestone in Congress’s steady march toward abject in­effectiveness.”

“It paints a portrait of dysfunction that further crystallizes for the American people their government’s incapacity for producing solutions to our major challenges,” Snowe said in a statement.

The supercommittee was created during this summer’s showdown over the federal debt limit, part of a two-stage strategy to restrain borrowing by at least $2.2 trillion over the next decade. About $1 trillion in savings was identified up front in the form of limits on spending that Congress appropriates annually. The committee was tasked with finding the rest, with the threat of $1.2 trillion in across-the-board cuts as an incentive to compromise.

Appointed by the four congressional leaders, the 12-member panel was given extraordinarily broad power to act. Any part of the budget was fair game. And if a majority of supercommittee members agreed on a plan, the House and the Senate would have to take it up for a vote without making changes.

Senate Minority Leader Mitch McConnell (Ky.) said Republicans considered the panel a “golden opportunity to change the direction of the nation’s fiscal trajectory and create a better environment for job growth.” In the end, however, the hard work of panel members was thwarted by the same political pressures that prevented Obama from sealing a far-reaching deficit deal this summer that he was negotiating with House Speaker John A. Boehner (R-Ohio).

Although Republicans offered to raise taxes by $300 billion over the next decade, they insisted on conditions that all but guaranteed that the wealthy would not be hit hard. And Democrats refused to agree to deep cuts in spending on health care for the poor and the elderly unless the rich were forced to make greater sacrifices.

By late last week, hope for a deal had all but faded, leaving panel members to spend a desultory weekend talking with their aides and trekking to TV studios for recrimination-filled appearances on Sunday talk shows. On Monday, several members took one last stab.

“Both sides are feeling angst and greater angst at the possibility of no agreement,” Sen. Max Baucus (D-Mont.) said as he left a midday meeting in the office of Sen. John F. Kerry (D-Mass.). “So they’re working harder, more creatively, to see what can be accomplished.”

In addition to Baucus and Kerry, the bipartisan huddle included Rep. Chris Van Hollen (D-Md.) and three Republicans: Rep. Fred Upton (Mich.) and Sens. Jon Kyl (Ariz.) and Rob Portman (Ohio).

Although the last-minute talks offered a ray of hope — a high school civics class from Georgia on a tour of the Capitol spent 40 minutes waiting outside Kerry’s office — aides to both parties said a deal was never close. But as late as 4:40 p.m., Kerry was still hoping for a bargain.

“Well, I can’t go into the details of it,” the senator told a TV reporter. “It’s sort of a last-ditch effort to try to see if we could find a way to solve America’s problem here.”

Kerry said the negotiators were “waiting for the chairs to speak” about whether the latest proposal would fly. Five minutes later, Murray and Hensarling issued their statement pulling the plug.

“I’m deeply disappointed with this outcome. We all are. This was an historic moment to do something big, bold, and balanced that demanded shared sacrifice to put our country first,” Kerry said later in a written statement.

“It’s too easy just to say that Washington is broken or Congress is broken,” he said. “These issues aren’t going away; in fact they are becoming more urgent.”

Staff writer Felicia Sonmez contributed to this report.