WASHINGTON (AP) -- A Democratic aide says the White House and congressional Republicans have reached an agreement to avert the so-called fiscal cliff.

The measure would extend Bush-era tax cuts for family incomes below $450,000 and briefly avert across-the-board spending cuts set to strike the Pentagon and domestic agencies this week.

Vice President Joe Biden was set to sell the agreement to Senate Democrats at a meeting at the Capitol on Monday night.

The aide required anonymity because he wasn't authorized to speak publicly.