WASHINGTON — During a rally in Montana Thursday, President Donald Trump suggested that his previous pick to run the Department of Veterans Affairs “didn’t really want to do it,” but would still have been an exemplary choice for the job.

He also accused the Senate Veterans Affairs Committee’s ranking member, Jon Tester, D-Mont., of being the ringleader of a smear campaign against his pick, former White House physician Rear Adm. Ronny Jackson, during his month as the nominee for the Cabinet post.

“Jon Tester showed his true colors with his shameful, dishonest attacks on a great man, a friend of mine,” Trump told the crowd at the event in Great Falls, packed with cheering supporters. “A man who I said, ‘Why don’t you run the VA, you’d be great?’”

“I put (Jackson) into the world of politics. How vicious is that world? But Jon Tester said things about him that were horrible and weren’t true.”

Jackson is currently under investigation by Navy officials for accusations of unprofessional behavior during his time at the White House Medical Unit that surfaced during his brief confirmation process.

Among the charges were reports made public by Tester in March that Jackson was allegedly careless with prescribing and handing out medication to White House staffers, bullied and insulted subordinates in the office, and abused alcohol during work hours, in one case crashing a government vehicle while intoxicated.

Jackson’s nomination had already raised concerns among veterans groups before those allegations because of his lack of experience with the VA system. When Republicans on the Senate veterans committee announced plans to delay his confirmation hearing amid the workplace accusations, he withdrew his name from consideration.

Jackson still works in the White House medical office but did not return to his post as the leader of that unit.

Trump repeatedly called him a “great family man” during the Montana event and appeared to claim that Jackson has been cleared of all the charges. Secret Service officials have disputed some of the accusations — in particular, they say they have no record of the the drunk driving incident — but Navy officials have not yet issued their investigation results.

The president also said he feels “guilty” for putting Jackson through the confirmation process.

“I said, ‘Doc, why don’t you run the VA? You’re a leader, you’re an admiral, people admire you.’ He’s an admired guy or I wouldn’t have done it,” Trump said.

“He said, ‘Sir, whatever your order, I will do it … If you ask, I will do it.’ But he didn’t really want to do it.”

The Jackson nomination saga was just part of Trump’s broad attack on Tester, who is up for re-election this fall. He is seen as one of the most vulnerable Democrats in the Senate, since Trump carried the state by more than 20 percentage points in the 2016 election.

The president attacked Tester for his opposition on a host of policy priorities, including border security, the nomination of Supreme Court Justice Neil Gorsuch, and health care reform.

For its part, Tester’s campaign in recent days took out several prominent statewide ads thanking the president for “supporting Jon’s legislation to help veterans and first responders, hold the VA accountable, and get rid of waste, fraud and abuse in the federal government.”

Jackson was nominated to replace former VA Secretary David Shulkin, who was fired from the post by Trump via Twitter after weeks of infighting at the department.

Jackson’s replacement was Pentagon Undersecretary for Personnel and Readiness Robert Wilkie, who had a confirmation hearing on June 27. Tester and other prominent members of the committee have already signaled their support for Wilkie to take over the post