Senate confirms top Treasury Department tax official

The Treasury building is seen in Washington, September 29, 2008.

WASHINGTON (Reuters) - The Senate has confirmed Mark Mazur as the Treasury Department's assistant secretary for tax policy, making him a top tax official in the Obama administration as major tax policy decisions lie ahead.

Nominated for the post in November by President Barack Obama, Mazur had been deputy assistant secretary for tax analysis. In his new job, he is likely to play a key role in tackling the "fiscal cliff" at the end of 2012 and possibly in renewed efforts to revamp the tax code in 2013.

Mazur takes on his new role as two other key tax players head out the door. Treasury Secretary Timothy Geithner and Internal Revenue Service Commissioner Doug Shulman are expected to step down soon, regardless of whether Obama is re-elected.

Mazur, confirmed late Thursday, will be the first Senate-confirmed assistant secretary for tax policy to serve in the Obama administration, now in its fourth year. Senate Republicans for years have blocked votes on a long list of Obama's nominees.

Republican Senator Charles Grassley, who has been advocating for reforms to the Internal Revenue Service's whistleblower office, briefly blocked Mazur's confirmation but dropped his opposition this week. Treasury oversees the IRS.

Mazur replaces Emily McMahon, who had been doing the top job on an acting basis since May 2011, when Michael Mundaca stepped down. Mundaca had occupied the post, also without Senate confirmation, since March 2010. Mundaca was preceded by Eric Solomon, who was appointed by former President George W. Bush.

Mazur joined Treasury in 2009. He previously worked at the IRS and for the President's Council of Economic Advisers under Bill Clinton.

"For the past decade, (Mazur) has worked on a wide-ranging and challenging set of tax issues and is held in high regard by his colleagues inside and outside government," Treasury Secretary Tim Geithner in a said statement on Friday.

The Senate also confirmed Matthew Rutherford as Treasury assistant secretary for financial markets, a role that oversees a wide range of financial regulatory issues. Rutherford previously worked at the Federal Reserve Bank of New York.

Senate Finance Committee Chairman Max Baucus, a Democrat, applauded both confirmations. "Mark Mazur will provide analysis that will help us get tax reform done right and spur broad-based growth," Baucus said in a statement.

(Reporting by Patrick Temple-West; Editing by Kevin Drawbaugh and Vicki Allen)