Palmieri has been reported to be in the running for a top communications job in former Secretary of State Hillary Clinton's expected presidential campaign. The White House declined to comment on her next move, and a spokesman for Clinton did not immediately return a request for comment.

Pfeiffer has advised Obama since his 2008 presidential campaign and is one of the last of the president's close confidants from that period to be leaving his immediate orbit.

"Like everyone else in the White House, I've benefited from his political savvy and his advocacy for working people," Obama said in a statement. "He's a good man and a good friend, and I'm going to miss having him just down the hall from me."

Pfeiffer is fond of sparring with reporters on Twitter and has spearheaded the administration's effort to use social media to spread its message, sometimes seeking to bypass traditional news organizations in the process.

Obama has been criticized for relying too much on an insular group of advisers, many from his Chicago-based campaign. But communication gurus such as David Axelrod and David Plouffe, who both spent stints in the White House after helping get him elected, have long since moved on.

Pfeiffer has experienced some health difficulties in recent years, including stroke-like symptoms.