US stocks dipped during a shortened Christmas Eve session Monday amid pessimism about prospects for a "fiscal cliff" deal by the end of the year.
The Dow Jones Industrial Average was down 51.76 points (0.39 percent) at 13,139.08.
The broad-market S&P 500 lost 3.49 points (0.24 percent) at 1,426.66, while the tech-rich Nasdaq Composite shed 8.41 points (0.28 percent) at 3,012.60.
The White House and lawmakers have until the end of the year to reach a deal to avert the so-called fiscal cliff, a combination of steep tax hikes and spending cuts due to take effect in January.
With the clock ticking, no compromise appears imminent. President Barack Obama and Congress are currently on Christmas break, but are expected to return to Washington later this week.
"US equities finished a quiet, shortened session in the red, as faith in lawmakers' ability to complete a deal to avert the so-called fiscal cliff continued to diminish with time running out," said analysts with Charles Schwab & Co.
Experts warn that going over the "cliff" could take the world's biggest economy back into recession.
Stocks in focus included online deals company Groupon, which dived 3.9 percent.
On Friday, Groupon announced it had acquired CommerceInterface, a provider of web-based channel management technology used in e-commerce operations, to enhance its Groupon Goods marketplace.
Shares of BlackBerry maker Research In Motion were down 2.8 percent after plummeting Friday on investor fears that its new smartphone platform will thin the ranks paying for its service.
Microsoft meanwhile was down 1.4 percent amid a report about tepid sales of its new Windows 8 software.
Investors also eyed oil companies Chevron and Apache, which announced plans to build a liquefied natural gas plant in Canada and jointly exploit shale gas fields there. Chevron lost just shy of one percent and Apache shed 1.7 percent.
Facebook gained 2.6 percent after analysts at Needham & Co raised their target price for the social media giant's stock.
Monday's bond prices fell. The 10-year US Treasury yield rose to 1.77 percent from 1.75 percent late Friday, while the 30-year climbed to 2.94 percent from 2.92 percent. Bond prices and yields move inversely.
After closing early on Monday, US markets will be closed Tuesday in observance of Christmas Day.