Obama Climate Adviser Browner to Step Down

White House energy and climate adviser Carol Browner plans to step down, officials confirmed to Fox News, marking the latest change-up at the highest levels of the Obama administration.

The move comes as President Obama prepares to deliver his State of the Union address at the halfway point of his term. He's scored significant legislative victories on the domestic front -- victories he will likely touch upon in his address -- but a comprehensive bill to address climate change is not among them. Browner, while successful in negotiating new fuel economy and greenhouse gas emissions standards with automakers, had not been able to shepherd such a package through Capitol Hill. After Republicans gained a majority in the House, Obama admitted the legislation to place a firm limit on greenhouse gas emissions was dead.

White House officials who confirmed Browner's departure would not say what will happen with the energy and climate office, but said it would be addressed as part of the White House reorganization. They said Browner is prepared to stay on as long as necessary to ensure a smooth and orderly transition.

Browner, a former Environmental Protection Agency administrator under President Bill Clinton, will be leaving the White House just as Republicans in Congress prepare to take on the Obama administration over global warming and the administration's response to the massive Gulf oil spill.

One White House official told Fox News that Browner is confident the mission of her office will remain critical to the president, and that she is pleased with references to clean energy expected to be in the State of the Union address and budget request.

Scott Segal, an energy lobbyist with Bracewell & Giuliani, said Browner's exit could "be a part of a legitimate effort to pay careful attention to addressing some of the real regulatory obstacles in the way of job creation."

Besides regulations to curb global warming, industry groups -- and Republicans on Capitol Hill -- are questioning a host of EPA rules targeting other air pollutants as job killers that will increase the costs of doing business.

And recently Browner's office had come under scrutiny for politicizing the response to the massive Gulf oil spill. The commission set up by Obama to investigate the disaster said Browner misconstrued on national television the findings of a federal scientific report by saying most of the oil was gone. The White House later said she misspoke.

Browner's office also has been criticized by the presidential panel for editing an Interior Department document in a manner that implied scientists supported the administration's decision to place a moratorium on deep water drilling. The commission found no evidence that the change made was intentional, and Interior Secretary Ken Salazar later apologized for the misunderstanding.

Browner's resignation comes amid a series of high-profile staff changes in Obama's White House.

The president has brought in a new chief of staff, Bill Daley, and is zeroing in on the choice of a new press secretary to replace the departing Robert Gibbs. Senior adviser David Axelrod is leaving the White House to focus on Obama's re-election, and both of Obama's deputy chiefs of staff are also leaving.

White House aides pushed back on a report that suggested Browner decided to leave after learning she would not be filling one of the deputy chief of staff positions. "Carol Browner never sought a deputy chief of staff slot," one aide said, calling that prospect "somewhat of a step down."

Staff members who are considering a change have been told to make their moves now or plan to stay for the remaining two years of Obama's term to ensure continuity.

Fox News' Mike Emanuel and The Associated Press contributed to this report.