Khan is accused of leaking a secret 'cable' sent to Islamabad last year by Pakistan's ambassador in Washington, which is the subject of the indictment.
A conviction for official secrets could carry a maximum sentence of 14 years in prison or even the death penalty, according to legal advisers.
Khan Faces Repeated Charges
Khan claims the 'cable' is evidence of a plot by the Pakistani military and the US government to overthrow his government in 2022, following his visit to Moscow just before the conflict in Ukraine.
Although his sentence was suspended, he remains behind bars on other charges, including inciting violence and a case involving official secrets. Khan's conviction in the bribery case also bars him from running for office, but his legal team is fighting for his release on bail and for the ban to be lifted.