The trial of Gupta, who is charged under the Official Secrets Act, began in-camera before additional sessions judge Pawan Kumar Jain, who recorded the testimony of two senior bureaucrats in the Ministry of External Affairs as prosecution witnesses.
At the outset, the judge asked all but Gupta, her counsel and the public prosecutor, to leave the court room.
A special secretary and a joint secretary in MEA recorded their statements today.
Gupta, 55, was posted as Second Secretary (Press and Information) in the Indian High Commission in Islamabad and was arrested on April 22, 2010, by the Special Cell of Delhi Police for leaking India's classified and defence-related information to ISI.
On January 7, she was charged under Section 3 and 5 of the Official Secrets Act for the lighter offences entailing maximum three years jail term, for allegedly supplying the country's information (not related to work of defence) to an ISI agent during her Islamabad posting.
While framing the charges, the court held the information leaked by Gupta did not fall under the category of work of defence, as opposed to the prosecution's case.
She was also charged with the breach of trust, criminal conspiracy and various other provisions of the Official Secrets Act.