United States President Barack Obama has confirmed that Chuck Hagel resigned as U.S. defence secretary after less than two years in the senior post.
According to the BBC, Obama paid tribute to Hagel's integrity and class.
Hagel, former Republican senator and a Vietnam war veteran said that it had been his life's greatest privilege.
He would stay on as secretary till his successor is confirmed.
Hagel has been quite critical of the U.S. strategy against the Islamic State and in retaliation to the Syrian regime.