Obama's energy adviser steps down
Carol Browner is stepping down as President Barack Obama's chief adviser on energy and climate matters, White House officials have said.
Ms Browner's resignation is expected to happen in the coming weeks.
The officials said she will stay on as long as is needed to ensure a smooth transition.
Ms Browner has been a central figure in the White House's strategy of trying to get a comprehensive energy bill passed, a matter that has stalled on Capitol Hill.
She was also a prominent voice in the administration's response to the oil spill in the Gulf of Mexico last year.
Her resignation comes amid a series of high-profile staff changes in Mr Obama's White House.