FILE - In this Nov. 29, 2016, file photo, President Barack Obama walks with his physician Dr. Ronny Jackson, right, towards a waiting Marine One as he leaves Walter Reed National Military Medical Center in Bethesda, Md., after visiting wounded service members. Now it’s Washington’s turn to examine Jackson. The doctor to Presidents George W. Bush, Barack Obama and now Donald Trump is an Iraq War veteran nominated to head the Department of Veterans Affairs. (AP Photo/Manuel Balce Ceneta, File)
FILE - In this Nov. 29, 2016, file photo, President Barack Obama walks with his physician Dr. Ronny Jackson, right, towards a waiting Marine One as he leaves Walter Reed National Military Medical Center in Bethesda, Md., after visiting wounded service members. Now it’s Washington’s turn to examine Jackson. The doctor to Presidents George W. Bush, Barack Obama and now Donald Trump is an Iraq War veteran nominated to head the Department of Veterans Affairs. (AP Photo/Manuel Balce Ceneta, File) Credit: Manuel Balce Ceneta

Washington — Ronny Jackson’s withdrawal from consideration to lead the Department of Veterans Affairs stanched an immediate political crisis for the Trump White House, but it sparked new questions over his future as the president’s doctor and the fate of the embattled agency.

Jackson announced on Thursday morning that he was pulling out of the nomination process amid a mushrooming cloud of allegations over professional misconduct, leaving in limbo a sprawling federal bureaucracy serving 9 million military veterans that President Donald Trump has called a top domestic priority.

Yet even as Jackson strongly denied the charges against him, calling them “completely false and fabricated” in a defiant statement, his position as Trump’s chief physician and a pending Navy promotion looked shaky. Congressional Democrats said the admiral’s nomination for a second star would not be considered until the Pentagon addresses allegations that he drank excessively on the job and oversaw a hostile working environment in the White House medical office, which he has led since 2013.

“If they had any merit, I would not have been selected, promoted and entrusted to serve in such a sensitive and important role as physician to three presidents over the past 12 years,” Jackson said of the charges.

The dramatic collapse of Jackson’s nomination to lead VA, the second-largest government agency behind the Pentagon, with 360,000 employees and a $186 billion budget, came after rapidly mounting questions over his qualifications and conduct. And it left the White House reeling to defend the nomination, which Trump made in surprise fashion after forcing out David Shulkin, a holdover from President Barack Obama’s administration, in March.

Although Jackson, 50, enjoyed significant support among Obama’s former aides, the onetime military trauma surgeon lacked management experience. Democrats demanded to know why Jackson, who offered a glowing public endorsement of Trump’s fitness at a January White House press briefing, had risen so quickly despite the outpouring of anonymously sourced accusations against him during the confirmation process.

Late Wednesday, the Democratic staff of the Senate Veterans’ Affairs Committee released a list of allegations, which included a claim that Jackson was intoxicated and crashed a government vehicle after a Secret Service goodbye party — a charge Jackson flatly denied. The office — which reports to the panel’s top Democrat, Jon Tester, of Montana — said the list of allegations was based on interviews with 23 of Jackson’s former and current colleagues, but it provided no specific evidence to substantiate the claims.