The Department of Defense Inspector General announced Wednesday it had initiated an investigation into Acting Defense Secretary Patrick Shanahan over reports that he has disparaged competing defense companies to the potential benefit of his former firm, Boeing.

In a statement announcing the investigation, IG spokeswoman Dwrena Allen said the agency “decided to investigate complaints we recently received that Acting Secretary Patrick Shanahan allegedly took actions to promote his former employer, Boeing, and disparage its competitors, allegedly in violation of ethics rules."

Last week, Citizens for Responsibility and Ethics in Washington filed an ethics complaint asking the IG to investigate the claims against Shanahan, to include reports that the acting defense secretary touted Boeing’s line of aircraft over rival Lockheed Martin.

Previous news reports indicated that Shanahan has disparaged Lockheed Martin’s fighter, the F-35, and other Lockheed weapons systems in private Pentagon meetings. In January, Politico reported that Shanahan called the F-35 “f---ed up” and reportedly said Lockheed “doesn’t know how to run a program.”

“We have informed him that we have initiated this investigation,” Allen said.

Acting Defense Secretary Patrick Shanahan goes before the Senate Armed Services Committee to discuss the Department of Defense budget, on Capitol Hill in Washington, Thursday, March 14, 2019. (J. Scott Applewhite/AP)

Shanahan spokesman Army Col. Joseph Buccino Shanahan welcomed the review.

“Shanahan has at all times remained committed to upholding his ethics agreement filed with the DoD,” Buccino said. “This agreement ensures any matters pertaining to Boeing are handled by appropriate officials within the Pentagon to eliminate any perceived or actual conflict of interest issue with Boeing.”

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The precarious perch of a potential Pentagon chief Patrick Shanahan, the former Boeing executive, was in a familiar place — aboard an airplane — when he got word of a bolt-from-the-blue political shot across his bow, an apparent blow to his chances of being nominated as the next secretary of defense.

In response to the investigation, Sen. Elizabeth Warren, D-Mass., said the reports of his Boeing comments concerned her. She added that even though Shanahan had officially recused himself from any decisions involving Boeing, he may not be able to truly be objective, given his long ties to the company.

“Your decades of work for Boeing might be influencing — either intentionally or unintentionally — your behavior toward the company and its competitors, and other employees at the Department that are responsible for contracting decisions that involve Boeing,” Warren wrote, asking Shanahan to follow up with her on any additional steps he planned to take to address the perceived bias.

Shanahan, 56, worked at Boeing for more than 30 years prior to being tapped by President Donald Trump to serve as deputy secretary of defense under former Defense Secretary Jim Mattis. When Mattis submitted his resignation in December, Shanahan was named by Trump as acting defense secretary.