Brian Deese, a senior White House budget aide, will replace the outgoing John Podesta as a top adviser to President Obama with a special focus on implementing Obama's climate-change and energy agenda in his final two years.
The 36-year-old Deese is currently the deputy director of the White House Office of Management and Budget and previously served as deputy director of the National Economic Council.
"As a part of his new role, Deese will take over the climate and energy portfolio that Podesta has handled—which will be one of the President's top priorities for the remainder of his term," a White House official said of Deese.
Deese will coordinate the administration's efforts to negotiate a new international climate pact in Paris late this year, the White House said. Deese will accompany Obama and other top officials on their trip to India, the world's third-largest greenhouse-gas polluter, later this week.
Podesta, a Democratic uber-strategist, is leaving the White House in February after a roughly yearlong push to implement and bolster Obama's second-term climate-change and energy plans.
Podesta is widely expected to play a major role in Hillary Clinton's likely presidential run.
A number of Obama's major environmental initiatives remained unfinished and face attacks from congressional Republicans, including Environmental Protection Agency carbon-emissions standards for power plants slated for completion this summer, and a new multiagency plan to cut leaks of the powerful greenhouse gas methane from oil and gas operations.
While Deese will focus heavily on energy and the environment, the role is broader.
"Deese will be part of the core White House strategic team, focusing specifically on bridging the intersection of policy, politics and legislative strategy going forward," the White House official said, adding that the role will include domestic and international policy and budget strategy.
Deese, at the National Economic Council, worked on topics ranging from tax policy to housing to auto policy to green energy, according to the White House.
"Brian is kind of the whole package—policy, strategy, insight to legislative and public affairs matters—and that's what the President was looking for," White House Chief of Staff Denis McDonough said in a statement.
Deese is a relatively young but trusted figure within the administration who, according to the White House, played a major policy-making role in preparation for Obama's State of the Union speech last night.
While Deese, who will have the title of senior adviser, will be hard-pressed to match Podesta's internal sway, environmentalists and progressive advocates cheered his appointment.
"Brian Deese is smart, creative, and close to the president, and he gets things done," said former White House climate czar Carol Browner, who is now with the Center for American Progress, the liberal think tank and advocacy group that Podesta founded in 2003.