Factbox: Trump administration departures, resignations and firings

U.S. President Donald Trump walks across the South Lawn after returning to the White House in Washington, U.S., December 7, 2018. REUTERS/Jim Young

WASHINGTON (Reuters) - Matthew Whitaker, acting U.S. attorney general since early November, would be replaced under plans announced on Friday by President Donald Trump, part of another staff shake-up at the highest levels of his turbulent administration.

Trump said he will nominate William Barr to permanently fill the top Justice Department post. Trump also said he will put forward State Department spokeswoman Heather Nauert as nominee to become ambassador to the United Nations, replacing current Ambassador Nikki Haley.

Both nominees would require confirmation by the Senate, which was unlikely to come until 2019.

Sources with direct knowledge of the situation said White House Chief of Staff John Kelly will soon resign. He and the president have frequently clashed.

Trump said he also would soon make changes at the Defense Department's Joint Chiefs of Staff. U.S. officials told Reuters that the Army's top general, Mark Milley, was expected to be the next chairman of the Joint Chiefs, in a decision that appears to be coming months earlier than expected. Milley would succeed Marine General Joseph Dunford, who would normally remain chairman until Oct. 1, 2019.

Here are some top people who have been fired or quit the administration since Trump took office on Jan. 20, 2017

2018

Matthew Whitaker - Named acting attorney general on Nov. 7, the Trump loyalist and former U.S. attorney in Iowa, replaced Jeff Sessions. Whitaker immediately came under scrutiny over past remarks critical of a probe into Russian meddling in the 2016 U.S. presidential election and any collusion between Moscow and the Trump campaign. As acting attorney general, Whitaker took over supervision of the probe led by Special Counsel Robert Mueller. Some lawmakers feared Trump might order Whitaker to undermine the inquiry, fears Trump allies called unwarranted.

Jeff Sessions - After months of being attacked and ridiculed by the president, the former senator was forced out on Nov. 7 as the top U.S. law enforcement official. Sessions earlier had been a major Trump supporter. But by recusing himself from supervising the Russia probe, he shifted that duty onto Deputy Attorney General Rod Rosenstein and incurred Trump's wrath.

Nikki Haley - She said on Oct. 9 she would step down at year-end as U.S. ambassador to the United Nations.

Don McGahn - Trump said in August the White House counsel would leave amid strains between the two over the Mueller probe.

Scott Pruitt - The Environmental Protection Agency chief quit on July 5 under fire over a series of ethics controversies.

David Shulkin - White House officials said on March 28 the Veteran Affairs secretary would resign. Shulkin had become a distraction due to a wave of speculation about his future.

H.R. McMaster - The national security adviser was replaced on March 22 with John Bolton, according to a Trump tweet.

Andrew McCabe - The deputy FBI director was fired in mid-March by Sessions. McCabe said he was targeted for being a witness into whether Trump tried to obstruct the Mueller probe.

Rex Tillerson - The secretary of state was fired by Trump on March 13 after rifts between them over international issues.

Gary Cohn - The National Economic Council director and former Goldman Sachs president said on March 5 he would resign, having lost a fight with Trump over tariffs.

Hope Hicks - The White House communications director, a long-serving and trusted Trump aide, resigned on Feb. 28.

Rob Porter - The White House staff secretary resigned in February after accusations of domestic abuse from former wives.

2017

Omarosa Manigault Newman - Fired as assistant to the president in December, the former reality TV star later wrote a book, "Unhinged: An Insider's Account of the Trump White House."

Richard Cordray - The U.S. Consumer Financial Protection Bureau's first director quit in November.

Tom Price - The Health and Human Services secretary quit under pressure from Trump on Sept. 29 over travel practices.

Stephen Bannon - Trump's chief strategist was fired by Trump in mid-August after clashing with White House moderates.

Anthony Scaramucci - The White House communications director was fired by Trump in July after 10 days on the job.

Reince Priebus - Replaced as chief of staff by John Kelly, Priebus lost Trump's confidence after setbacks in Congress.

Sean Spicer - Resigned as White House press secretary in July, ending a turbulent tenure.

Walter Shaub - The head of the U.S. Office of Government Ethics, who clashed with Trump, stepped down in July.

Michael Dubke - Resigned as White House communications director in late May.

James Comey - The FBI director, who led the Russia probe before Mueller, was fired by Trump in May.

Katie Walsh - The deputy White House chief of staff was transferred out to a Republican activist group in March.

Michael Flynn - Resigned in February as Trump's national security adviser after disclosures that he discussed U.S. sanctions on Russia with the Russian ambassador to the United States before Trump took office. Flynn later pleaded guilty to lying to the FBI. He is set to be sentenced in December.

Sally Yates - Trump fired the acting U.S. attorney general in January after she ordered Justice Department lawyers not to enforce Trump's immigration ban.

(Reporting by Washington Newsroom; Editing by Kevin Drawbaugh and Jonathan Oatis)