The Obama administration announced Wednesday the creation of a task force to propose major changes in the tax code.

The group will be an offshoot of the president’s Economic Recovery Advisory Board, which is led by former Federal Reserve Chairman Paul Volcker and staffed by Austan Goolsbee, a University of Chicago economist who advised Obama’s campaign. Among the likely members who will focus on taxes will be former Clinton economic adviser Laura Tyson, Harvard professor Martin Feldstein, former Securities and Exchange Commission Chairman William Donaldson and Roger Ferguson, chief executive of TIAA-CREF.

The panel will report back to Obama by Dec. 4, said Peter R. Orszag , director of the Office of Management and Budget. That would give lawmakers and the administration time to begin planning for the tax legislation needed to make the changes.

At the end of 2010, all of the Bush administration tax cuts enacted in 2001 and 2003 (PL 107-16, PL 108-27) will expire, meaning that if Congress does nothing, income taxes will rise sharply for most Americans. In addition, Obama’s Making Work Pay tax credit for lower- and middle-class Americans that was enacted as part of the economic recovery package (PL 111-5) last month also expires at the end of 2010.

“The only constraints on its activities are that there will be no tax increases during 2009 or 2010, and the proposals should not raise taxes on American families making less than $250,000,” Orszag said.

Congress already dealt with some of its most pressing 2009 tax issues in the stimulus package, which included extensions through this calendar year of a number of popular business tax breaks such as bonus depreciation and expanded small business expensing.

More significantly, perhaps, the stimulus measure also carried a “patch” to keep the alternative minimum tax from hitting an estimated 26 million additional taxpayers this year. That spares Congress what has become an annual battle over whether to offset the cost of the AMT patch with tax increases elsewhere.

President George W. Bush created a tax panel in 2005, charged with overhauling the entire tax code. But after the panel released its recommendations, Bush never spoke about it and did not attempt to advance any of its recommendations through Congress.

Orszag said the task force will focus on three areas: tax simplification, reducing “corporate welfare” and shrinking the estimated $290 billion a year “tax gap” between taxes owed and taxes paid.

The tax gap, Orszag said, “is a lot of money. And we are interested in being as aggressive as possible in trying to reduce that number.”

That focus will be hailed by Senate Finance Chairman Max Baucus , D-Mont., who has repeatedly called for greater IRS attention on the tax gap.

In the corporate arena, some Democrats, notably Ways and Means Chairman Charles B. Rangel , D-N.Y., have called for pairing a corporate tax rate reduction with the elimination of tax preferences, such as the ability of companies to defer taxes on income earned overseas.

Obama’s budget counts on $210 billion from some of those same revenue-raisers to help shrink the deficit over the next few years.