WATCH LIVE: Biden welcomes Defense Secretary Hagel to Pentagon

Hagel, a former GOP senator from Nebraska, was confirmed by the Senate late last month on a 58-41 vote after one of the most contentious confirmation fights for a Defense secretary in U.S. history.

Obama's pick for Defense chief drew the ire of Republicans for Hagel's controversial statements on Israel, Iran and other issues. In the end, only four GOP senators voted in support of Hagel.

Since taking office, Hagel has traveled to Afghanistan, where he met with President Hamid Karzai. During the trip, Hagel denied Karzai’s claims that the U.S. and Taliban were holding secret talks.

"The fact is, any prospect for peace or political settlements — that has to be led by the Afghans. That has to come from the Afghan side," Hagel said, according to reports. "Obviously, the United States will support efforts if they are led by the Afghans to come to some possible resolution."

The Defense secretary faced questions this week about a guilty verdict in an Air Force sexual assault case that was overturned.

House Armed Services Committee Chairman Buck McKeon (R-Calif.) and ranking member Adam Smith (D-Wash.) sent a letter to Hagel on Thursday requesting an explanation about a sexual assault case at Aviano Air Base in Italy in which Air Force Lt. Gen. Craig Franklin tossed out Lt. Col. James Wilkerson’s year sentence and dismissal.

They also asked Hagel about the underlying authority a commander has in the military judicial system to single-handedly overturn verdicts and suggested they were considering changes to the system in this year’s Defense authorization bill.

Jeremy Herb contributed to this report.