The court said David Headley should disclose the "full and true facts" leading to 26/11 attacks; he should also reveal the role he and others played in the attacks.

Headley should disclose the facts he has already admitted before the court in Illinois and reveal if any of the attackers were involved in other attacks in India, the court also said.

Accepting his role in the attacks, Headley, who is serving a 35-year jail term in the US for the 26/11 attacks, said, "I pleaded guilty in the past to the charges in the US and I admitted I was a participant in these charges... I appear here ready to answer questions regarding these events, if I receive a pardon from this court."

In December 2011, the National Investigation Agency had filed a charge-sheet accusing Headley, his Pakistani-Canadian accomplice Tahawwur Rana, Lashkar founder Hafiz Saeed and seven others of conspiracy. The charge carries death penalty.

Atul Kulkarni, senior police officer of Mumbai, told NDTV, "After weighing the pros and cons, we decided we will get more from him (Headley) by having him as an approver than as an accused considering his plea bargain agreement in the US. All the necessary people have been kept in the loop."

The police wants to question Headley regarding the involvement of Pakistan army and its Inter-Services Intelligence.

Earlier, during his questioning by officers of India's National Investigation agency, Headley allegedly said three senior Pakistan army officers played a prime role in the 26/11 attacks.

The same Pakistani officers were reportedly named by Lashkar terrorist Abu Jundal, the alleged mastermind of the 26/11 attacks, against whom charges were framed last month in Mumbai.

Pakistan has repeatedly rejected the charge that its army officers were involved in the attacks. It put seven men on trial, including Lashkar commander Zaki-ur-Rahman Lakhvi. The trial has been on for seven years, raising charges of tardiness from India. Earlier this year, Lakhvi was granted bail, creating fresh tension between Pakistan and India.