US President-elect Donald Trump has jettisoned a respected national security expert from his transition team in a sign that he may be settling on loyalists such as former New York City Mayor Rudy Giuliani and conservative ideologues such as former UN Ambassador John Bolton to staff his administration.
Mike Rogers, a former US congressman from Michigan who headed the House of Representatives intelligence committee, said he was leaving the transition team.
His sudden departure was announced four days after New Jersey Governor Chris Christie was abruptly replaced as the head of Trump's transition team by Vice President-elect Mike Pence.
Giuliani and Bolton are being considered for secretary of state, according to sources close to Trump.
Giuliani, New York's mayor at the time of the September 11, 2001, attacks by Islamist al-Qaida militants, is known as a hard-liner on national security matters.
Bolton is also a foreign policy hawk who said last year the United States should bomb Iran to halt its nuclear program.
With fewer than 70 days until his January 20 inauguration, the Republican president-elect has little time to settle on Cabinet members and other senior appointees.
Trump, who had never previously run for office until his surprise victory over Democrat Hillary Clinton last week, will eventually need to fill roughly 4000 open positions.
Pence has not yet filled out paperwork required by law to work on the transition with Democratic President Barack Obama's outgoing administration, the White House said.
Two national security officials said Trump's operation had been slow to get up to speed and had not yet deeply engaged with security and intelligence agency personnel who were ready to start helping them out.
A former Republican government official said Rogers' exit from the transition team was part of a purge of relatively moderate individuals who had worked on the transition with Christie before Pence took over.
Some prominent Republican experts who might be tapped to fill out a Trump administration, meanwhile, were warning colleagues to steer clear.
"After exchange w Trump transition team, changed my recommendation: stay away. They're angry, arrogant, screaming 'you LOST!' Will be ugly," former State Department official Eliot Cohen wrote on Twitter.