President Barack Obama has made official the news that's been known for days: Rahm Emanuel, his hard-charging chief of staff, has resigned.
"Welcome to the least suspenseful announcement of all-time," joked Obama in a East Room news conference Friday.
The president said goodbye to chief of staff and wished him well as he "explores other opportunities" — a coy reference to Emanuel's anticipated mayoral campaign in Chicago.
The president lauded Emanuel as an "incomparable leader" and a "selfless public servant." He added, "We could not have accomplished what we've accomplished without Rahm's leadership."
Obama also announced that Pete Rouse, a deeply trusted senior adviser to the administration, has been named interim White House chief of staff. The president called him a "skillful problem solver.
At the White House event, Emanuel called it a "bittersweet day." He thanked the president for his "warm friendship and confidence."
"Mr. President, I thought I was tough," Emanuel told Obama. "I want to thank you for being the toughest leader any country could ask for in the toughest times any president has ever faced."
Referencing his well-known penchant for profanity during his White House tenure, Emanuel also told the president: "I'm sure you've heard some words you've never heard before."
Emanuel appeared to choke up as he spoke of his family's immigrant background, and the opportunities he's been afforded.
"I want to thank you for the opportunity to repay, in some small portion, the blessings that this country has given to my family ... I give you my word, that even as I leave the White House, I will never leave that spirit of service behind."
Emanuel never directly mentioned that he was running for mayor, and Obama didn't either. Emanuel, sure to be cast as an outsider by his competitors in the upcoming mayoral campaign, did not want to announce his run from Washington.
But Emanuel did call Chicago "the greatest city in the greatest country in the world." And he told Obama, "I'm energized by the prospect of new challenges, and eager to see what I can do to make our hometown even greater."
Rouse, befitting his style, stood quietly by the president and never spoke. Obama described him as never seeing a television camera or a microphone that he liked — unlike the boisterous Emanuel. The differences were even apparent on stage — Rahm with his trademark hands on hips, Rouse still and stoic.
Rahm's parting gift
Emanuel leaves behind more than a staff job. It is the most demanding and influential position in the White House — save for Obama's. The person who holds it is entrusted to shape the president's thinking, prioritize his time, manage scores of egos and issues and keep the White House focused on its goals.
Emanuel gave a teary-eyed farewell to his senior staff members earlier Friday after receiving a gag gift of an enormous, dead Asian carp, sources in the White House told NBC News. He received the fish from administration official Austan Goolsbee (a fellow Chicagoan who volunteered on Rahm's first campaign for Congress).
"I know that I pushed you all very hard," he said in a five-minute-long goodbye speech. "But I did it in service to the president and I believe that our whole country is better off for it."
The permanent replacement? Rouse is considered a leading choice to become the permanent chief of staff. So is Tom Donilon, the deputy national security adviser known as a skilled interagency manager, although he may be a logical replacement for national security adviser James Jones upon his expected departure in the coming months. Another top candidate is Ron Klain, although he might be reluctant to leave his job as Vice President Joe Biden's chief of staff.
Obama's choice comes in the context of a personnel reorganization, two years into a grueling presidency, with some key players already planning to leave the White House grind and others likely seeing changes in their portfolio. The results of the Nov. 2 House and Senate midterm elections will also be a factor.
Emanuel and Rouse could not be more different in their personalities and style. Emanuel, 50, is a fast-moving, disciplined and notoriously profane manager — the once and future politician who served as an Illinois congressman and always had a longing for running for mayor of his hometown Chicago.
Rouse, 64, shuns the spotlight but has quietly built up an enormous wealth of trust and relationships in Washington. Those close to him say that he provides what Obama needs — a sharp and strategic mind, a sense of continuity, a knack for troubleshooting and an ability to keep people focused on their tasks. Rouse served for years as chief of staff to then-Senate Democratic leader Tom Daschle and is known on Capitol Hill, but he won't be found schmoozing at political dinners.
The plan within the White House is that some of Emanuel's responsibilities will be shared among other senior officials, not just Rouse. White House officials also say it is a strength that Rouse will bring his own style to his job and that every White House expects change and needs it.
Over the last three decades, White House chiefs of staff have typically served for two to three years.
Obama, after winning a seat to the Senate, recruited Rouse to be his chief of staff there and ultimately made him a top adviser in the White House.
The move pits Emanuel against a growing field of local politicians vying for the Windy City job that will be vacated next spring by Mayor Richard M. Daley, who announced in early September that he will not seek a seventh term. Emanuel's victory in the race is no given, with rivals certain to attack the longtime political operative and former congressman as a brusque outsider who belongs more to Pennsylvania Avenue than Michigan Avenue.
NBC News' Savannah Guthrie contributed to this story.