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Ousted Secretary of Veterans Affairs David Shulkin is ripping the “toxic, chaotic, disrespectful and subversive” environment of Washington after being canned by President Trump this week.

“As many of you know, I am a physician, not a politician,” Shulkin wrote in a blistering New York Times op-ed published after his firing. “I came to government with an understanding that Washington can be ugly, but I assumed that I could avoid all of the ugliness by staying true to my values.”

On Wednesday, the president announced plans to replace Shulkin with Rear Adm. Ronny Jackson, the White House physician.

TRUMP LOOKS TO REPACE DAVID SHULKIN WITH ADM. RONNY JACKSON AS VETERANS AFFAIRS SECRETARY

Rumors had been swirling for weeks about Shulkin's future amid investigations into alleged spending abuses and reports of internal dissension at the VA.

In February, the VA's internal watchdog found that Shulkin had improperly accepted Wimbledon tennis tickets and his then-chief of staff had doctored emails to justify his wife traveling to Europe with him at taxpayer expense. Shulkin agreed to reimburse the government more than $4,000 in that case.

But in his op-ed, Shulkin claimed to be the victim of “politically-based attacks.”

“I have been falsely accused of things by people who wanted me out of the way,” Shulkin said. “But despite these politically-based attacks on me and my family’s character, I am proud of my record and know that I acted with the utmost integrity. Unfortunately, none of that mattered.”

He said the toxic environment recently had made it hard to do his job.

I have fought to stand up for this great department and all that it embodies,” he said. “In recent months, though, the environment in Washington has turned so toxic, chaotic, disrespectful and subversive that it became impossible for me to accomplish the important work that our veterans need and deserve.”

He suggested his ouster could be related to those who want to privatize the VA – something he opposes.

“They saw me as an obstacle to privatization who had to be removed,” he said.

It marked the latest in a string of swift White House replacements in recent months. Most recently, Trump ousted Rex Tillerson from the State Department and announced plans to replace him with CIA Director Mike Pompeo.

Shulkin’s exit is reminiscent of Tillerson’s – with both avoiding directly speaking about President Trump while also expressing bitterness at being fired.

“As I prepare to leave government, I am struck by a recurring thought: It should not be this hard to serve your country,” Shulkin said.

Fox News’ Sam Chamberlain and The Associated Press contributed to this report.