Congress leader Rahul Gandhi on Wednesday termed as a "big step" the Supreme Court appointing a three-member panel of cyber experts to probe the alleged use of Israeli spyware Pegasus for surveillance of certain people, and expressed confidence that truth would come out.

At a press conference here, Gandhi alleged that only the prime minister or the home minister could have ordered the use of Pegasus spyware.

During the last Parliament session, the Opposition had jointly taken up the issue and had stalled proceedings demanding a probe, he recalled.

"We were asking three basic questions -- who authorised Pegasus, which agency, which person authorised Pegasus as we all know Pegasus cannot be bought by a private individual, it has to be bought by a government; second question was who was it used against; final thing was, did any other country have access to information of our people," the former Congress chief said.

Asserting that alleged snooping using Pegasus is an "attempt to crush Indian democracy", Gandhi said it is a "big step that the Supreme Court has said that they are going to look into this matter. I am confident that we will get the truth out of this".

"We are quite happy that the Supreme Court has accepted to look into this. There is the institution of Parliament where we will raise this again and we will try to have a debate in Parliament. I am sure the BJP will not like that debate so they will make sure that debate is stalled but we will try to hold that debate," he said.

The Supreme Court on Wednesday appointed a three-member panel of cyber experts to probe the alleged use of Israeli spyware Pegasus for surveillance of certain people in India, saying every citizen needs protection against privacy violation and mere invocation of "national security by State" does not render the court a "mute spectator".

Finding material that "prima facie merits consideration", a bench comprising Chief Justice N V Ramana and Justices Surya Kant and Hima Kohli declined the Centre's plea to appoint an expert panel on its own, saying such a course would violate settled judicial principle against bias.

Three experts on cyber security, digital forensics, networks and hardware were roped in by the Supreme Court to "enquire, investigate and determine" whether Pegasus spyware was used for snooping on citizens and their probe would be monitored by former apex court judge R V Raveendran.

The three-member technical panel, which has been given wide ranging powers, would comprise eminent experts, Naveen Kumar Chaudhary, Prabaharan P and Ashwin Anil Gumaste and report to Justice Raveendran.