Chuck Hagel (l) is to step down as US defence secretary
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Hagel: 'It's been the greatest privilege of my life'

Chuck Hagel has announced he is to resign as US defence secretary after less than two years in the top military post.

Mr Hagel, 68, a Vietnam war veteran and former Republican senator, said the role had been the "greatest privilege" of his life.

President Barack Obama confirmed his resignation and paid tribute to his "class and integrity".

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