Updated

WASHINGTON -- The federal budget deficit rose to $150.4 billion last month, the largest November gap on record. And the government's deficits are set to climb higher if Congress passes a tax-cut plan that's estimated to cost $855 billion over two years.

The Treasury Department says November's budget gap was 25 percent more than the deficit in November 2009. Much of last month's jump, though, was due to a quirk of the calendar determining when benefit checks are mailed.

For the first two months of the current budget year, which began Oct. 1, the deficit totals $290.8 billion. That's 2 percent less than for the same period a year ago. And economists had been estimating that the full-year deficit would decline after two years of record highs.

But analysts say the tax deal President Barack Obama reached with Republicans this week will give the 2011 budget year the largest deficit in history -- $1.5 trillion, according to economists at JPMorgan Chase. It would mark the third straight year of trillion-dollar-plus deficits.

Under the tax-cut plan, JPMorgan economist Michael Feroli said he expects a $1.5 trillion deficit this year to be followed by a $1.2 trillion gap in 2012.

The 2009 deficit is the current all-time high, at $1.42 trillion. The second-highest deficit ever is the $1.29 trillion deficit for the 2010 budget year, which ended Sept. 30.