On Tuesday, the court had asked Pakistan to put Mr Jadhav's death sentence on hold. It said it would hear the case on Monday. Senior advocate Harish Salve, who represents India at the International Court, has said its judgment will be binding on Pakistan.
At a meeting with legal experts on Thursday, attended by Pakistan's Attorney General, it was decided that Pakistan would adopt a three-point strategy - the first of which will involve challenging the jurisdiction of the International Court with regard to this particular case, sources said.
India and Pakistan signed up for the "Optional Protocol to the Vienna Convention on Consular Relations concerning the Compulsory Settlement of Disputes, 1963," which says such disputes are within the compulsory jurisdiction of the International Court.
But Pakistani officials are counting on the instance in June 2000, when the International court had agreed with India that it had no jurisdiction to hear a case filed by Pakistan, accusing India of shooting down an unarmed aircraft of the Pakistani navy the year before. India had argued that it was an internal matter, which was accepted by the court.
Pakistan also plans to ask for more time from the court and as for another date for hearing. It plans to present what it calls the "evidence" against Mr Jadhav. There were only five days between the letter from the International court and the hearing set for May 15.
India has said it was a "carefully considered decision" to go to the world court - a first in 45 years - to save the life of an Indian citizen. India has rubbished Pakistan's claims that Mr Jadhav was arrested from Pakistan's restive Baluchistan province and he was in the country to spy for intel agency Research and Analysis Wing.
In its appeal to the world court, India said Mr Jadhav, a retired Naval officer, was running a business in Iran from where he was abducted. Pakistan rejected India's repeated appeals for consular access, sentenced Mr Jadhav to death and failed to inform India formally, the appeal said.