India has appealed to the International Court of Justice (ICJ) to order Pakistan to suspend the execution of a retired Indian naval officer convicted of espionage.
Deepak Mittal, joint secretary of India's Foreign Ministry, told the court in The Hague on May 15 that the death sentence handed down to Kulbhushan Jadhav last month followed an "unjust" trial in a Pakistani military court.
He said that Pakistan failed to respond to Indian demands for information about the case.
But Pakistan's representative Muhammad Faisal told the tribunal that Jadhav had "confessed to having been sent by India to wage terror on the innocent civilians and infrastructure of Pakistan."
Faisal, from the Pakistani Foreign Affairs Ministry, said the court had been shown a video of the confession which was available online "for viewers to decide for themselves whether Commander Jadhav is confessing voluntarily."
Faisal showed the court a photograph of a passport which he said was found in Jadhav's possession bearing a completely different "and Muslim" name.
"India has been unable, or perhaps unwilling, to provide an explanation for this passport which is the most obvious indication of covert and illegal activity," Faisal said.
Jadhav's arrest and trial has further strained tense relations between the nuclear-armed neighbors.
Pakistani officials say Jadhav was arrested in the southwestern province of Balochistan in 2016.
India denies Jadhav was a spy and claims he was kidnapped from Iran. It lodged a protest at the ICJ last week, accusing Islamabad of "egregious violations" of the Vienna Convention On Consular Relations.
With the case expected to take months or years to resolve, New Delhi is calling on the international court to order Islamabad to prevent Jadhav's execution pending the final outcome.
The court's president has already written to Pakistan urging it to refrain from steps that could affect the hearings, effectively a request to prevent the execution from taking place.