Washington's debt just keeps on piling up, according to a government agency that predicted the federal budget will hit near record spending levels for the second time in two years.

The Congressional Budget Office estimated this year's federal deficit will reach about the same as last year's at $1.3 trillion - equal to about 8.6 percent of gross domestic product.

Economists warn the deficit should only rise to about three percent.

In fiscal 2009, the debt equaled 10 percent of the U.S. economy, the CBO said.

The U.S. Treasury Department will issue the official fiscal 2011 deficit number later this month.

The national debt now stands at $14.9 trillion and interest payments on the debt shot up last year to $266 billion.

The congressional supercommittee has been charged to find cuts amounting to at least $1.2 trillion over 10 years.

But economists say it'll take a far larger deficit-cutting effort to ease the dangers that future deficits pose to the economy.