Chuck Hagel, the former Republican senator from Nebraska, was sworn in as secretary of defense Wednesday after a bruising nomination fight.

Hagel took oath in a private ceremony at the Pentagon on his first day at work and will make remarks to service members and civilian employees of the department later Wednesday morning.

The new defense secretary arrived at the Pentagon about 40 minutes late from his scheduled arrival time of 7:30 a.m. ET.

Shortly after being approved Tuesday afternoon by the Senate -- following a long confirmation battle with Republican senators who opposed some of his previous statements and positions -- Hagel released a statement about his new job.

"I am honored that President Obama and the Senate have entrusted me to serve our nation once again," the statement read. "I can think of no greater privilege than leading the brave, dedicated men and women of the Department of Defense as they perform vital missions around the globe. I will work closely with Congress to ensure that we maintain the strongest military in the world and continue to protect this great nation."