Washington (CNN) President Donald Trump has re-nominated his former physician Rear Adm. Ronny Jackson to receive a second star, even as he remains under Pentagon investigation over allegations of improper behavior.

The President's push for Jackson to get a bump in his military rank comes less than a year after Jackson withdrew from consideration as Trump's nominee for secretary of Veterans Affairs over allegations that he was "abusive" toward colleagues, loosely handled prescription pain medications and was periodically intoxicated.

Jackson denied all of the allegations leveled against him, calling them "completely false and fabricated."

Despite the nomination, Jackson is unlikely to receive his military promotion while the Defense Department's inspector general investigation remains active. The Senate Armed Services Committee is not expected to consider the nomination until the investigation is completed, which is typical of military nominees who are the subject of an active investigation, according to two Senate aides. Senate Armed Services Chairman Jim Inhofe's office did not respond to a request for comment.

"The White House is the one who resubmitted his nomination to the Senate and so we'll see -- there's an investigation going on, that's in progress so all of these things have to kind of culminate to see where we go," said Adm. John Richardson, the chief of naval operations.

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