In virtual unanimity, commission members one by one agreed that the US budget deficit and national debt loomed as an imminent threat to the very foundations of the nation.

But there was broad disagreement on the plan by the commission's co-chairmen to raise the Social Security pension retirement age, slash spending and increase the motor fuel tax. Co-chairman former Sen. Alan Simpson warned "the denizens of darkness" are poised to fight the panel's recommendations.

While members of the commission showed an unusual breadth of bipartisanship, deep differences remained and forced Simpson and fellow panel leader Erskine Bowles to delay a vote on the document until at least Friday.

For years, US politicians have failed to act on the country's growing deficit spending.

That was particularly evident during the administration of former President George W. Bush, who started wars in Iraq and Afghanistan, cut taxes and raised drug benefits for the elderly without devising a way to pay for the increased spending.

That deep deficit hole grew only deeper as Obama took charge in the White House as the country was lashed by the worst economic downturn and financial crisis in eight decades. Government spending to prevent a second Great Depression rivaling the one in the 1930s pushed the red ink to an astronomical level.

Washington is watching with alarm the financial turmoil that is gripping Europe as a result of unsustainable government debt. Those concerns may leave American politicians — no matter how politically dangerous — to take some action.

Unless US indebtedness begins declining, international investors — countries like China — could demand higher interest payments which would only compound American debt.

The new plan by deficit commission Simpson and Bowles, proposes raising the retirement age to receive Social Security government pension benefits, cutting the Medicare health care plan for the elderly, curtailing tax breaks and doubling the federal tax on gasoline.

"... There's no easy way out," said Bowles. "For us, it's go big or go home," he said. "This problem is just too plain big, and too important for our country. The plan that you have before you is one that Alan and I are proud of," Bowles said.

Divisions among the 18 commission members left the plan unlikely to win enough bipartisan support to be approved for an automatic vote in Congress this year.

But two members who are elected senators, Democrat Kent Conrad and Republican Judd Gregg, became the first to endorse it despite voicing reservations.

Bowles had already declared victory, saying he and Simpson have at least succeeded in initiating an "adult conversation" in the country about the pain it will take to cut the deficit.

Bowles was White House chief of staff when former President Bill Clinton negotiated a balanced budget plan in 1997; Simpson is a former Republican senator from Wyoming and known for his colorful straight talk.

Obama named the commission in hopes of bringing a deficit-fighting plan up for a vote in Congress this year, but it appears to be falling well short of the 14-vote bipartisan supermajority needed. When Congress comes back in January, Republicans will hold a majority in the House of Representatives, taking over from Obama's Democrats.

Details of the recommendation include a gradual increase in the Social Security retirement age to 68 by 2050 and 69 by 2075, using a less generous cost-of-living adjustment for the programs and raising the amount of income subject to Social Security taxes.

The plan also retains an increase on gasoline of about 15 cents per gallon (4 cents per liter), a three-year freeze on federal worker pay and the elimination of 200,000 workers from the federal payroll through attrition.