WASHINGTON - US ambassador to the United Nations Nikki Haley, a highly visible face of Donald Trump's administration on the world stage, is the latest top official to exit the president's inner circle.
Dozens of White House aides – from press secretary Sean Spicer to chief of staff Reince Priebus to counsel Don McGahn – have either left or been sacked from their posts since Trump took office on January 20, 2017.
Here is a sampling of senior departures:
UN Ambassador Nikki Haley
Haley was a shining star of the administration from the start. Thrust onto the international stage, she quickly became an astute advocate for Trump's foreign policy, using forceful language against North Korea, Syria and Iran.
The former South Carolina governor was also unafraid to speak her mind, often in fairly undiplomatic language, and built a reputation for standing up to Trump when she felt it was warranted.
Her aggressive criticism of Russia won plaudits, even as she stepped beyond the position held by the White House.
Her Tuesday announcement dramatically boosted speculation about her political future. But she quickly denied any plans to challenge her boss in 2020, instead saying it was "time to stand aside" and that she would remain loyal to Trump.
Environment chief Scott Pruitt
Environmental Protection Agency head Scott Pruitt's tenure was beset by scandal, and Trump pushed him out in July.
A former Oklahoma attorney general with ties to fossil fuel industries, Pruitt was accused of using his position to enrich his own family's lifestyle in violation of federal law.
Secretary of State Rex Tillerson
Rex Tillerson was fired by Trump in March, ending a rocky tenure for the former Exxon chief executive as the nation's top diplomat.
Tillerson was frequently at odds with the mercurial president and Trump said that while the pair got along well, they "disagreed on things" – notably the Iran nuclear deal, from which Trump withdrew in May.
During his brief stay at Foggy Bottom, Tillerson frequently found himself out of the loop and caught unawares by policy shifts announced in Trump tweets.
Chief Strategist Steve Bannon
The architect of Trump's nationalist-populist campaign and his election victory, White House chief strategist Steve Bannon was nicknamed the Prince of Darkness and the Shadow President.
His economic nationalism became the lynchpin of Trump policies, even as many of Bannon's other ideas were rebuffed by policy rivals.
Bannon's constant clashes with other advisors became untenable, as did his ties to the extreme right, which drew accusations that Trump fostered racists. Bannon left in August 2017.
Top Economic Advisor Gary Cohn
Gary Cohn, a former president of investment bank Goldman Sachs, resigned as Trump's top economic advisor on March 6, 2018 in protest against the president's decision to levy new global trade tariffs.
A long-time Democrat, Cohn had always been an uneasy fit in an administration propelled to power by strident nationalism.
National Security Advisors Flynn, McMaster
Michael Flynn, a retired lieutenant general, was being investigated for his contacts with Russians and eventually pleaded guilty to lying to the FBI.
He lasted only 22 days as national security advisor, ousted amid concerns he could be compromised by false statements he made over his contacts with Russian officials.
Flynn's replacement HR McMaster, also a lieutenant general, lasted barely a year. He never really clicked with the president, who bristled at McMaster echoing the US intelligence establishment consensus that Russia meddled in the 2016 election.