WASHINGTON — White House chief of staff Ron Klain is expected to leave the Biden administration in the coming weeks, according to two sources familiar with the decision.

Klain has held the top job for more than two years and was a key adviser to Biden during the 2020 campaign. It had long been expected that he would leave sometime after the midterms and the plan is for him to do so after the speech. Biden’s State of the Union address early next month, said the sources who spoke on condition of anonymity.

As the first departure among a stable core of senior advisers closest to the president, Klain’s departure is likely the first domino in a series of personnel moves to come. Advisers have long said a wave of them would likely come after the State of the Union on Feb. 7, with parallel moves as part of a campaign surge.

The move comes at a critical time for the Biden White House, as congressional investigations ramp up and a potential 2024 reelection gets underway, but it also doesn’t come as a surprise to those who work with Klain. “No one is surprised,” said an administration official.

Several replacements are already being considered, according to two sources with knowledge of the discussions. Among the candidates are current senior adviser Anita Dunn, counselor to the president Steve Ricchetti, former Covid-19 coordinator Jeff Zients and former Delaware Governor Jack Markell.

Klain declined to confirm or deny the news of his impending departure, which was first reported by The New York Times. “We don’t have any announcements at this time,” she told NBC News on Saturday afternoon.

Klain, who has been the president’s chief of staff since his inauguration and has worked with Biden for decades, is credited with bringing calm discipline and order to West Wing operations, which have been remarkably drama-free.

Biden’s cabinet has seen no change, nor has there been the backbiting or turf wars that were a feature of daily life in former President Donald Trump’s White House.

Sen. Chris Coons, D-Del., would not confirm or deny Klain’s reported plans to leave. But he said Klain has been an indispensable part of the political successes Biden has racked up.

“Ron Klain’s talent, energy, integrity and skills have been critical to the accomplishments of the past two years,” said Coons, who is close to Biden’s White House. «He is relentlessly loyal to the president, he has a clear vision of the challenges of advancing his agenda, and he is unmatched in his work ethic.»

“The unprofessionalism and utter chaos of the Trump White House have been largely forgotten in the circles I work in,” Coons added. “It seems we are back to normal. There are adults in the room.

Chris Whipple, who wrote a book on White House chiefs of staff and recently published a new book on the Biden White House, ranked Klain as one of the best chiefs of the modern presidency. Others, he said, were James Baker, who was chief of staff to former Republican Presidents Ronald Reagan and George HW Bush; and Leon Panetta, who served under former Democratic President Bill Clinton, Whipple said.

“It is a great challenge for Joe Biden to choose a successor to Ron Klain,” Whipple said. “Those are huge shoes to fill. Klain belongs to an elite company among the best White House chiefs of staff.»

“You have to know how to run the White House; you have to know Capitol Hill inside out; and you have to be able to drive the president and drive up and down. She is in a 30-year relationship with Joe Biden. They were like an old married couple.»

A president’s first chief of staff typically stays in office for about two years. Trump replaced his first chief of staff, Reince Priebus, early, just six months after taking office. Former President Barack Obama’s first chief of staff, Rahm Emanuel, left after the midterm elections.

mike memoli Y kristen welker contributed.