Washington: US Deputy Secretary of Defence William Lynn has announced his intention to step down and return to private life, the Pentagon said.

Lynn, 57, met Secretary of Defence Leon Panetta recently to discuss his plans, as reported in daily news.

At Panetta's request, he has agreed to remain in his post until a successor takes his place.

Lynn has provided outstanding advice and counsel to this department and to the nation in course   of his long career. I will rely on his experience and expertise during this transition period,' said Panetta.

Lynn has been the Pentagon's No.2 official since February 2009. During his nearly two-decade career of government service, he served as senior national security advisor to late senator Edward Kennedy and as senior advisor to five secretaries of defence.

'It has been a rare privilege to serve in the Department of Defence during such a challenging time,' said Lynn.

'And it has been an honor to serve alongside an outstanding group of civilian and military members who every day demonstrate the value to this nation of their unwavering commitment and dedicated service.'