(Reuters) - Senate leaders have not yet been able to reach a deal to a avert a "fiscal cliff," and with time running out, it is uncertain if they will get one, a senior Senate aide said on Sunday.

Senate Majority Leader Harry Reid and Senate Minority Leader Mitch McConnell have been aiming to reach an agreement by 3 p.m. EST (2000 GMT) so that they can present it to previously scheduled closed-door meetings of their respective Democratic and Republican colleagues in an attempt to beat a New Year's Day deadline.

However, at this point, they still do not have an agreement, the aide said, speaking on condition of anonymity. (Writing by Thomas Ferraro; Editing by David Brunnstrom)