Senior BJP leaders including LK Advani have been asked to respond to a petition that asks the Supreme Court to restore conspiracy charges against them in the 1992 Babri mosque demolition.
Mr Advani and the others - MM Joshi, union minister Uma Bharti and Rajasthan governor Kalyan Singh - have been given four weeks to respond to the court's notice.
In 2010, the Allahabad High Court dropped conspiracy charges against these leaders for the razing of the 16th century mosque in Ayodhya, Uttar Pradesh, by Hindu activists.
A petition by Haji Mehboob Ahmed, a defendant in the Ayodhya lawsuit, wanted those charges to be reinstated. Senior Congress leader Kapil Sibal argued his case in court.
The court has also given the CBI more time to prepare its case in support of its appeal against the high court order.
In 2001, a lower court dropped the conspiracy charge against the leaders on the ground that the case related only to the volunteers who razed the mosque. This was upheld by the High Court.