WASHINGTON, Nov 9: David Petraeus, Director of the Central Intelligence Agency (CIA), has resigned, citing ‘personal reasons’ in his resignation letter to President Barack Obama, the White House said on Friday.

“David Petraeus has provided extraordinary service to the United States for decades,” said US President Barack Obama in a message issued by his office. “Today, I accepted his resignation as Director of the Central Intelligence Agency.”

(News agencies quoted Mr Petraeus as saying that he had shown “extremely poor judgment by engaging in an extra-marital affair”.

In a message to the CIA workforce he said: “After being married for over 37 years, I showed extremely poor judgment by engaging in an extra-marital affair.

“Such behaviour is unacceptable, both as a husband and as the leader of an organisation such as ours,” Petraeus said.)Mr Obama called Mr Petraeus one of the outstanding general officers of his generation who helped the American military adapt to new challenges, and led American men and women in uniform through a remarkable period of service in Iraq and Afghanistan, where he helped “our nation put those wars on a path to a responsible end”.

Mr Petraeus took over as CIA chief on Sept 6 last year. Before joining the CIA, he was a four-star general and served over 37 years in the US Army. His last assignments in the Army were as commander of the International Security Assistance Force (ISAF) and Commander of US Forces in Afghanistan from July 4, 2010, to July 18, 2011.

Media speculated earlier this year that Mr Petraeus was interested in running for the presidency, noting that he had visited a school known for hosting presidential debates, New Hampshire’s Saint Anselm College.

Although Mr Petraeus said he had no interest in politics, media continued to say that he will be a good Republican presidentialcandidate.