The White House would be taking a risk if it tries to make a constitutional end-run around Congress' authority to raise the debt ceiling, legal experts said.

The "public debt" clause of the 14th Amendment is being cited by a number of lawmakers as giving President Barack Obama a legal way to issue debt and pay bills, working around the debt ceiling and avoiding default.

The 14th Amendment is best known for extending civil rights protections in the wake of the Civil War.

 The amendment's fourth section was designed to guarantee Union debt incurred during the war, including compensation due to Union soldiers and their widows.

The clause states: "The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned."

On Friday, Senate Democratic leaders told Obama to be ready to take "any lawful" steps to ensure that the United States did not trigger a global economic crisis.

Obama has said he would not negotiate with Republicans in Congress on the debt ceiling, increasing the prospect that they may try to block an increase in the borrowing limit.

Democrats hope to avoid a replay of the 2011 debt ceiling deadlock that pushed the country to the brink of default.

One congressional aide said using the provision was the only potential option available to Obama if Congress balks.

But some legal scholars say the provision does not give the president the authority to raise or ignore the $16.4 trillion debt cap.

"I don't think the language of the 14th Amendment authorizes it," said Erwin Chereminsky, professor at University of California Irvine School of Law.

 "The debt ceiling is set by statute, and the president can't change statutes unilaterally."

Eric Posner, a University of Chicago law professor, said the provision is vague and "does not implicitly give the president authority to do anything."

"It's not a very strong legal argument," Posner said.

The public debt section's only Supreme Court test, in 1935, had nothing to do with the debt ceiling.

"Nobody really knows what would violate that section (the 14th Amendment) since it's so far removed from what the original idea was," said Gerard Magliocca, a professor at Indiana University School of Law.

 "There's not much law on it, so it's really hard to come up with any firm conclusions."

On Dec. 31, the Treasury reached the limit on how much it is legally allowed to borrow and is now using emergency maneuvers to continue paying government bills such as interest on U.S. bonds and military salaries.

Those measures, which include tapping certain government pension funds, are due to run their course around mid-February, giving Congress around five weeks to raise the ceiling.

The debt limit only allows the Treasury to borrow funds to pay for existing obligations that Congress and the president have already agreed upon.

Although Congress has routinely increased the limit since it was established in 1917, it has become more contentious since annual federal budget deficits have been topping $1 trillion, with conservatives in Congress using it as leverage to demand spending cuts.

BACK-UP PLANS

With fears that Congress will not act in time, the 14th Amendment provision has surfaced as a backup plan along with another offbeat proposal to mint a trillion dollar platinum coin.

Although the White House has said it does not believe that there is a constitutional workaround for the debt ceiling, Obama has repeatedly said he will not negotiate with Republican lawmakers who want to win concessions on federal spending before agreeing to a debt limit increase.

That has raised speculation that the Democratic president will eventually be forced to rely on the Constitution to avoid a debt default and ensuing havoc on global financial markets.

Even if Obama tried to move forward without congressional approval, the action could come too late to shore up investor confidence if it is already shattered. Bonds could be challenged as unconstitutional.

"The Treasury market is viewed as the largest, most liquid and from a credit stand point, the least risky market in world," said Ward McCarthy, chief financial economist at Jefferies & Co.

McCarthy said if the credibility of the United States were to take a hit, that market would lose all of those attributes.