The Supreme Court adjourned an appeal hearing on Tuesday into the death sentence handed down to Ajmal Kasab, the lone surviving gunman from the 2008 Mumbai attacks.
Kasab, one of 10 gunmen who laid siege to Mumbai in attacks which lasted nearly three days and killed 166 people, has appealed for his sentence to be overturned after he was convicted in May 2010.
The 24-year-old Pakistani was found guilty of a series of crimes, including waging war against India, murder and terror acts.
The November 2008 attacks saw 10 heavily-armed Islamist gunmen storm targets including luxury hotels, a Jewish centre and a train station.
One of the two Supreme Court judges due to hear the appeal was unavailable on Tuesday, forcing the adjournment, officials said. No date was immediately set for the next hearing.
Kasab's court-appointed lawyer Raju Ramachandran told AFP that his job was "a call of duty", but declined to talk further about the case.
India blames the Pakistan-based Lashkar-e-Taiba (LeT) militant outfit for training, equipping and financing the attack with support from "elements" in the Pakistan military.
Kasab's death sentence was confirmed by a state high court in Mumbai last year. If he loses his Supreme Court appeal, he will be able to appeal for clemency from the president.
Ujjwal Nikam, who prosecuted the case in Mumbai on behalf of the Maharashtra state, is seeking to push through the death sentence.
"This is the rarest of rare cases," Nikam told AFP. "He should not be entitled to any mercy."
At the trial, the prosecution produced fingerprint, DNA, eyewitness and television evidence showing him opening fire and throwing grenades at Mumbai's main railway station in the bloodiest episode of the attacks.
Kasab -- who is in jail in Mumbai -- initially pleaded not guilty but later made a confession, admitting to being one of the gunmen sent by the banned LeT militant group.
He then reverted back to his initial denial and said he was framed by the police.
Pakistan has indicted seven alleged perpetrators over the attacks but they have not been brought to trial, triggering Indian accusations that the process is a sham.
Pakistani investigators and lawyers will visit India next month to gather more evidence ahead of any trial in Islamabad.
Most death sentences in India are commuted to life imprisonment, and convicts can sit on death row for years awaiting a final decision.