Retired US General David Petraeus may face retroactive demotion for telling state secrets to his one-time mistress because Defense Secretary Ashton Carter wants to get tough on misbehaving military chiefs, according to a published report. A demotion could cost the former respected head of the US forces in Afghanistan hundreds of thousands of dollars in pension money over his lifetime.

Petraeus retired from the Army in 2011 as a four-star general and stepped down as director of the Central Intelligence Agency a year later, after his affair with Paula Broadwell was exposed. Broadwell was a military officer who was working on Patreaus' biography at the time. Now Petraeus may be retroactively demoted, three sources have told the Daily Beast. Carter is reportedly considering ignoring an earlier recommendation by the Army that Patraeus not have his ranked reduced.

"The secretary is considering going in a different direction" from the Army, a defense official told the Daily Beast, because he wants to be consistent in his treatment of all senior officers who engage in misconduct.

Pentagon spokesman Peter Cook said the Army was "in the process" of providing Carter with information relevant to former Army Secretary John McHugh's recommendation not to demote Petraeus. "Once the secretary‎ has an opportunity to consider this information, he will make his decision about next steps, if any, in this matter," Cook said.

The Washington Post reported in December 2015 that it would be "unusual" for Carter to overrule the Army. But US Attorney Jill Westmoreland Rose later told the Charlotte Observer that no final decision had yet been made about military punishment for Petraeus and Broadwell, who's currently an Army reservist.

Patraeus could be busted from a four-star general to lieutenant general, and have his pension reduced from about $220,000 (£154,000) to $170,000 (£119,000) a year. There are only a dozen four-star generals in the US.

Petraeus pleaded guilty in 2015 to giving Broadwell eight notebooks that he compiled while commander of the US forces in Afghanistan and which contained extremely sensitive classified information, including the identities of covert officers and notes on his discussions with President Obama. He could have faced felony charges but was allowed to plead guilty to a misdemeanor count of unauthorized handling of classified information. He avoided a prison sentence but received two years probation and a $100,000 (£70,000) fine in a North Carolina court.

He is currently collecting speaking fees and is working for a private equity firm.