Former US Army general and CIA director David Petraeus -- the man once in charge of US military strategy in both Iraq and Afghanistan -- has pleaded guilty to mishandling classified material.

Petraeus was once one of the most respected figures in American public life -- only to fall spectacularly amid revelations he had an affair with his biographer, Paula Broadwell.

That scandal hit another level when allegations arose that Petraeus may have shared classified information with Broadwell.

Now, the plea deal recommends a $40,000 fine and two years of probation - and an all-but-assured end to a career in public life that many saw as possibly leading to the White House.