WASHINGTON (AP) — House Democrats said Wednesday that President Barack Obama should invoke a little-known constitutional provision to prevent the nation from going into default if Congress fails to come up with a plan to raise the debt ceiling.

Rep. James Clyburn of South Carolina, a member of the Democratic leadership, said he told fellow Democrats that Obama should both veto any House GOP plan for a short-term extension of the debt ceiling and invoke the 14th amendment, which says that the validity of the nation's public debt "shall not be questioned."

The White House has rejected resorting to this tactic to keep the nation from defaulting, questioning its legality, but Rep. John Larson of Connecticut, who chairs the Democratic caucus, said "we're getting down to decision time" and "we have to have a failsafe mechanism and we believe that failsafe mechanism is the 14th Amendment and the president of the United States."

Larson said Clyburn's proposal on the 14th Amendment was met with applause by other Democrats at their meeting.

The Democratic leaders said the vast majority in their party still support a plan for raising the debt ceiling and cutting spending put forth by Senate Majority Leader Harry Reid. But they said the inability of the government to pay its debts could drive up interest rates and affect millions of Americans forced to pay higher mortgages and higher interest on student loans.

Rep. Xavier Becerra of California, the assistant caucus chair, said Democrats are telling Obama, "Mr. President, Republicans through their failure have given you license to do whatever it takes to not let the American family go down into that abyss with House Republicans."

The post-Civil War 14th Amendment guaranteeing citizenship to all people born or naturalized in the United States contains a provision that "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."

Some legal scholars have said the president can invoke that clause to keep the nation from defaulting on the debt, although there is no legal precedent for such an action.