Updated

Christina Romer, one of President Obama's top economic advisers, plans to step down effective Sept. 3.

Romer, head of the president's Council of Economic Advisers, has been one of the administration's most prominent voices on the economy, making frequent appearances on TV and at White House events to promote Obama's policies. She also was reported to have butted heads with other members of Obama's economic team, in particular Larry Summers, director of the National Economic Council.

In December, the she sand Summers even seemed to contradict each other -- in interviews conducted on the same day -- on whether the recession had ended.

"Everybody agrees that the recession is over," Summers said.

"Of course not," Romer said in a separate interview.

More On This...

The clash appeared at the time to speak not just to the differing views on the economy within Obama's inner circle but also to the sharply conflicting signals out of the economy itself, which continues to struggle to rebound.

Her resignation comes as the White House labors to convince the public that the economy is on the right track amid near-double digit unemployment.

"Christy Romer has provided extraordinary service to me and our country during a time of economic crisis and recovery," Obama said in a written statement. "The challenges we faced demanded more of Christy than any of her predecessors, and I greatly valued and appreciated her skill, commitment and wise counsel.

The White House cast Romer's decision as an unsurprising one driven by family reasons: Romer plans to return to California, where her son will be starting high school. She also is returning to the University of California, Berkley as an economics professor.

One administration official, speaking to the Associated Press on condition of anonymity to discuss internal relations at the White House, downplayed any tension between Romer and Summers, saying the pair often emerged as strong allies.

Summers said Monday night that Romer has been "an extraordinary friend and colleague at the White House," and he looked forward to drawing on her advice in the future.

The Associated Press contributed to this report.