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.
Browner successfully helped negotiate a deal with automakers boosting federal fuel economy standards and requiring the first-ever greenhouse gas emissions standards for vehicles. She also pushed for billions of dollars for renewable energy in the economic stimulus bill.
But the administration fell short on it key domestic priority of passing a comprehensive energy and climate bill to place a firm limit on the pollution blamed for global warming. Just after the November elections, which gave Republicans a majority of seats in the House, Obama admitted the legislation was dead.
One White House official said Monday that Browner was "confident that the mission of her office will remain critical to the president." The official, speaking on the condition of anonymity, said Browner was "pleased" with the clean energy commitment Obama would lay out in his State of the Union address Tuesday and in his 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 Interior Department inspector general for editing a 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.
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.