Obama hails outgoing Hagel

Barack Obama spent almost 10 minutes thanking Chuck Hagel for his "six decades" of service to the United States, most recently his almost two years in the top job at the Pentagon. Hagel submitted his letter of resignation to Obama on Monday morning.

"When I nominated you for this position, you said you would always give me your honest advice and informed council. You have," Obama said. "You have always given it to me straight."

Obama told reporters that Hagel first confided that he was considering stepping down in October, saying that they had concluded it was an "appropriate time" for him to complete his service. He pointed out Hagel's own history as a Vietnam veteran, praising his close connection with US servicemen and women over the years.

"Chuck Hagel has devoted himself to our national security and our men and women in uniform across six decades," Obama said.

Calling the 68-year-old former Republican Senator "an exemplary defense secretary," Obama also recalled their time spent together a decade ago on the US Senate Defense Committee; the president described himself as still a "green-behind-the-ears senator" at the time, working with his Republican counterpart.

"On behalf of a grateful nation, thank you, Chuck," Obama concluded.

Hagel to stay until successor confirmed

Hagel said at the conference that "to lead and to serve" had been the "greatest priviledge of my life." He noted the difficult reforms at the Pentagon during his brief tenure, as Washington tries to juggle restructuring and budget changes with the wind-down of combat operations in Afghanistan, the battle against the self-proclaimed "Islamic State," the conflict in Ukraine, ebola, and a planned shift in security focus to the Asia-Pacific region. However, Hagel said that the reforms, unpopular in some quarters, would "prepare this institution for the challenges facing us in decades to come."

"I will stay on this job and work just as hard as I have over the couple of years - every day, every moment - until my successor is confirmed by the United States Senate," Hagel said.

Hagel's possible replacements

US newspaper the New York Times, which first reported Hagel's impending resignation, mooted three potential substitutes: Michele Flounoy, former under secretary of defense; Ashton Carter, a former deputy secretary of defense; and Democrat Senator Jack Reed of Rhode Island.

Obama and Hagel did not stay for questions after the press conference.

Hagel's successor will need to go through the confirmation process in the US Senate, facing questions and then a vote from lawmakers in the upper chamber of Congress. As of midterm elections earlier this month, the opposition Republicans now control the long-Democrat-held Senate. Hagel's own confirmation process was a fairly fractious affair.

msh/shs (AFP, AP, Reuters)