Defense Secretary Chuck Hagel has resigned from President Barack Obama's cabinet

By RYAN GORMAN

Defense Secretary Chuck Hagel has stepped down, reportedly under pressure from the White House.

Hagel's resignation was announced Monday in a statement to the military obtained by the Washington Post. The move came at the behest of President Barack Obama, sources told the New York Times.

"You should know I did not make this decision lightly," Hagel said in the statement. "But after much discussion, the President and I agreed that now was the right time for new leadership here at the Pentagon."

Hagel was the only Republican advising the president on defense matters.

The decision to relinquish his post was made Friday by Hagel, the Times reported. It came after weeks of meetings and despite assurances by his aides that the 68-year-old was committed to finishing out his four-year term.

Hagel is seen by the president as not being able to handle the unique challenges that come with trying to dismantle the Islamic State. The U.S. Army lifer was brought in to manage the troop withdrawal from Afghanistan under a shrinking military budget, the paper noted.

"We have prepared ourselves, our Allies and the Afghan National Security Forces for a successful transition in Afghanistan," Hagel said of that effort.

"The next couple of years will demand a different kind of focus," an unnamed official told the Times, adding that Hagel was not fired, but offered his resignation after it became apparent he was not the right man for the job going forward.

Hagel's critics have in the past been quick to point out that he is mostly silent during cabinet meetings and often waited to speak with the president when both men were alone. Sources speculated this was a result of him not being able to command the same attention as holdovers from Obama's campaign staff.

After less than two years on the job, Hagel appeared to wither into the shadow of Joint Chiefs of Staff, General Martin Dempsey, who was outspoken in his recommendation of military action against ISIS.

Sources told the paper that Obama chose Hagel mainly to carry out his wishes after General Robert Gates, his predecessor, openly criticized the president following his four-year term in both a book and subsequent media appearances.

Hagel's criticism of the president only came in recent months after he disagreed with officials over the scope of the threat posed by ISIS.

But Hagel seemed to counteract those assertions.

"We have taken the fight to ISIL and, with our Iraqi and coalition partners, have blunted the momentum of this barbaric enemy," said the outgoing defense secretary.

As Obama confidantes called the group a junior varsity basketball team, Hagel referred to them as an "imminent threat to every interest we have ... beyond anything that we've seen."

Those comments were called "unhelpful" by the White House.

Hagel is out, but has vowed to stay in place until a new successor is named.

Possibilities include Michele Flournoy, a former under secretary of defense, and Ashton Carter, a former deputy secretary of defense, according to Reuters. Both were rumored to be contenders for the job before Hagel was appointed.

Democratic Senator Jack Reed, from Rhode Island, is another possible contender, Reuters reported.

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