Some US lawmakers have been voicing concern that the country would go over 'the fiscal cliff' in the next week, triggering harsh spending cuts and tax hikes.
Some Republicans claimed that was President Barack Obama's goal.
"It's the first time that I feel it's more likely that we will go over the cliff than not," Senator Joe Lieberman, an independent from Connecticut, said on CNN's "State of the Union."
"If we allow that to happen it will be the most colossal consequential act of congressional irresponsibility in a long time, maybe ever in American history."
The Democratic president and Republican House of Representatives Speaker John Boehner, the two key negotiators, are not in contact and are out of town for the Christmas holidays.
Congress is in recess, and will have only a few days next week to act before January 1st.
On the Sunday TV talk shows, no one signalled a change of position that could form the basis for a short-term fix, despite a suggestion from Obama on Friday that he would favour one.
The focus was shifting instead to the first days of January when the lowered tax rates dating back to President George W. Bush's administration will have expired, presenting Congress with a redefined and more welcome task that involves only cutting taxes, not raising them.
Some Republicans have said President Obama would welcome the fiscal cliff's tax increases and defence cuts, as well as the chance to blame Republicans for rejecting a deal.
The President has rejected that assertion.
Democrats claim that Mr Boehner has his own self-interested reasons for avoiding a deal before January 3rd when the House -elected on November 6th - is sworn in and casts votes for a new speaker.
Markets could tumble
The most immediate impact could come in financial markets, which have been relatively calm in recent weeks as Republicans and Democrats bickered, but could tumble without prospects for a deal.
Markets will be closed on Tuesday for Christmas.
Wall Street will resume regular stock trading on Wednesday, but volume is expected to be light throughout the week with scores of market participants away on a holiday break.
If Congress fails to reach any agreement, income tax rates will go up on just about everyone on January 1st.
Unemployment benefits, which Democrats had hoped to extend as part of a deal, will expire for many as well.
In the first week of January, Congress could scramble and get a quick deal on taxes and the $109 billion in automatic spending cuts for 2013 that most lawmakers want to avoid.
Once tax rates go up on Jan. 1, it could be easier to keep those higher rates on wealthier taxpayers while reducing them for middle- and lower-income taxpayers.
Lawmakers would not have to cast votes to raise taxes.