Following a request by Sen. Marco Rubio (R-FL), the Transportation Department Office of Inspector General (OIG) will review a total of 18 flights covering seven trips made by Transportation Secretary Pete Buttigieg on aircraft operated by the Federal Aviation Administration (FAA).

In total, the flights — dating back to 2017 — cost $41,905.20 in taxpayer money for Buttigieg and the other staff onboard. A department spokesperson told Reuters that operating the FAA planes was cheaper than flying commercial in six of the seven trips.

The spokesperson added that the department intends to “fully cooperate with the [Inspector General] on this,” according to Reuters.

In January, the month after Rubio’s initial request, Sen. Chuck Grassley (R-IA) also raised concerns about Buttigieg’s travel arrangements.

“Brief meetings with people you could have met with in Washington, or picked up a phone to talk to, create questions about whether you really required the use of a private jet, especially as you call on Americans to sacrifice to reduce carbon emissions,” Grassley wrote.

For his part, Buttigieg said on Twitter he was “[g]lad this will be reviewed independently so misleading narratives can be put to rest.”

“Bottom line: I mostly fly on commercial flights, in economy class. And when I do use our agency’s aircraft, it’s usually a situation where doing so saves taxpayer money,” tweeted the Transportation secretary.

The OIG said it would “focus on official trips taken since January 31, 2017,” Reuters reported.

Part of that period was occupied by the former Transportation secretary, Elaine Chao, who served in the role under President Trump.

Rubio prompted the focus on the Transportation secretary’s flights in December 2022. The senator initiated the request after Fox News reported on the trips, questioning if Buttigieg failed to follow department policies when using FAA aircraft.

“American taxpayers deserve assurances that their tax dollars are not wasted by the government’s highest officials,” wrote the senator, per Reuters.

A spokesperson for the Transportation secretary, Kerry Arndt, said in an email that the review will offer his team an opportunity to address “some of the false, outlandish, and cynical claims about the Secretary’s mode of travel,” according to The Washington Post.