President Donald Trump fired Veterans Affairs Secretary David Shulkin and nominated White House doctor Ronny Jackson to replace him following a bruising ethics scandal and a mounting rebellion within the agency.

A Navy rear admiral, Jackson is a surprise choice to succeed Shulkin, a former Obama administration official and the first nonveteran to head the VA. Trump had been considering replacing Shulkin for weeks but had not been known to be considering Jackson for the role.

In a statement, Trump praised Jackson as “highly trained and qualified.” It was a decision that signaled Trump chose to go with someone he knows and trusts, rather than choosing a candidate with a longer resume, to run a massive agency facing huge bureaucratic challenges.

Shulkin said he was undone by advocates of privatization within the administration. He wrote in a New York Times opinion piece that they “saw me as an obstacle to privatization who had to be removed.” He added: “That is because I am convinced that privatization is a political issue aimed at rewarding select people and companies with profits, even if it undermines care for veterans.”

Jackson has served since 2013 as the physician to the president, one of the people in closest proximity to Trump day in and day out.

His profile rose after he conducted a sweeping press conference about the president’s medical exam in January in which he impressed Trump with his camera-ready demeanor and deft navigation of reporters’ questions as he delivered a rosy depiction of the president’s health, according to a person familiar with the president’s thinking but not authorized to discuss private conversations.

Jackson eagerly embraced the idea of moving to the VA, according to a White House official who spoke on condition of anonymity to discuss personnel matters. Ironically, it was Shulkin who had recommended Jackson for an undersecretary position at the agency in fall. Jackson was vetted during that time on his policy positions and other issues, the official said.

The promotion of Jackson marks the latest Trump hire to be driven at least as much by personal familiarity with the president as by his vision for the role at government’s second-largest department, responsible for 9 million military veterans in more than 1,700 government-run health facilities.

Brig. Gen. Dr. Richard Tubb, who trained Jackson, said in a letter read at Jackson’s briefing that the doctor had been attached like “Velcro” to Trump since Inauguration Day.

“On any given day,” he wrote, “the ‘physician’s office,’ as it is known, is generally the first and last to see the President.”

A White House official said Shulkin was informed of his dismissal by chief of staff John Kelly before the president announced the move on Twitter on Wednesday.

A major veterans’ organization expressed concern over Shulkin’s dismissal and Trump’s intention to nominate Jackson, whom they worried lacked experience to run the huge department.

“We are disappointed and already quite concerned about this nominee,” said Joe Chenelly, the national executive director of AMVETS. “The administration needs to be ready to prove that he’s qualified to run such a massive agency, a $200 billion bureaucracy.”

Rep. Phil Roe, chairman of the House Veterans Affairs Committee, said he believed Shulkin did a “fantastic job” and didn’t think he should have been dismissed, but “at the end of the day, Cabinet secretaries serve at the pleasure of the president.”

“I respect President Trump’s decision, support the president’s agenda and remain willing to work with anyone committed to doing the right thing on behalf of our nation’s veterans,” said Roe, a Republican from Tennessee.

Shulkin is the second Cabinet secretary to depart over controversies involving expensive travel, following Health and Human Services Secretary Tom Price’s resignation last September. Trump said in a statement he is “grateful” for Shulkin’s service.

Shulkin had agreed to reimburse the government more than $4,000 after the VA’s internal watchdog concluded last month that he had improperly accepted Wimbledon tennis tickets and that his then-chief of staff had doctored emails to justify his wife traveling to Europe with him at taxpayer expense. Shulkin also blamed internal drama at the agency on a half-dozen or so rebellious political appointees, insisting he had White House backing to fire them.

But the continuing VA infighting and a fresh raft of watchdog reports documenting leadership failures and spending waste — as well as fresh allegations that Shulkin had used a member of his security detail to run personal errands — proved too much of a distraction.

It was the latest in a series of departures of top administration officials, including Secretary of State Rex Tillerson and national security adviser H.R. McMaster.

The VA change comes as Trump is trying to expand the Veterans Choice program, fulfilling a campaign promise that major veterans’ groups worry could be an unwanted step toward privatizing VA health care. His plan remains in limbo in Congress.

Having pushed through legislation in Trump’s first year making it easier to fire bad VA employees and speed disability appeals, Shulkin leaves behind a department in disarray. Several projects remain unfinished, including a multibillion-dollar overhaul of electronic medical records aimed at speeding up wait times for veterans seeking medical care as well as expanded mental health treatment for veterans at higher risk of suicide.

Trump selected Robert Wilkie, undersecretary of defense for personnel and readiness, to serve as the acting head of the VA.