India has warned Pakistan that its conduct will be under watch and any "farcical attempts" claiming to implement the ICJ's order in the Kulbhushan Jadhav case would mean going back to the world court or the UN Security Council for remedies.
Jadhav, 49, a retired Indian Navy officer, was sentenced to death by a Pakistani military court on charges of "espionage and terrorism" in April 2017 based on an "extracted confession". India had moved the International Court of Justice (ICJ), the principal judicial organ of the United Nations, to seek a stay on his death sentence and further remedies.
A 16-member bench headed by President of the Court, Judge Abdulqawi Ahmed Yusuf, by 15-1 votes ordered Pakistan on Wednesday to undertake an "effective review and reconsideration" of the conviction and sentence of Jadhav.
"It is a good moment for us to help Jadhav get justice and ensure he gets a fair trial," India's lead counsel in the case, Harish Salve, told reporters in London on Wednesday in the the wake of the judgment.
Salve indicated that the next steps would involve access to the Indian national by India's consular officials in Pakistan, who will then be able to ensure he gets full legal representation.
Asked about the means at India's disposal if Pakistan did not fully comply with the ICJ verdict, he noted: "If there is a violation of the order, we can go back to the ICJ to seek further instructions. If a country brazenly violates such an order, there are other provisions, including sanctions in the [UN] Security Council and other remedies.
"I am sure Pakistan would not go that way, or at least I hope so.... Their conduct is under watch and any farcical attempts will not go unnoticed... If a country decides to behave rogue and not comply, there are measures available."
"There is an obligation of result, of fair adjudication after allowing Mr Jadhav consular access and Pakistan must take all steps necessary, including legislative measures," the senior Indian lawyer asserted.
Reacting for the first time to the verdict, Pakistan Prime Minister Imran Khan on Thursday tweeted: "Appreciate ICJ's decision not to acquit, release and return Commander Kulbhushan Jadhav to India. He is guilty of crimes against the people of Pakistan. Pakistan shall proceed further as per law."
In its 42-page ruling, the ICJ ruled that Pakistan had "breached" the Vienna Convention on diplomatic relations, which gives countries the right to consular access when their nationals are arrested abroad.
The world court found that by not informing Jadhav without delay of his rights under Article 36 of the Vienna Convention on Consular Relations, Pakistan breached the obligations incumbent upon it under that provision.
"The judgment has restored our faith in the rule of law, in the ICJ and in the systems which we as mankind put together to protect the citizens of the world," said Salve.
"We had challenged the conduct of Pakistan in its brazen refusal to adhere to the Vienna Convention and allow consular access to Mr Jadhav... The court found Pakistan guilty of internationally wrongful acts and that it must cease those acts," he said.
The ICJ has declared that Pakistan is under an obligation to inform Jadhav without further delay of his rights and to provide Indian consular officers access to him in accordance with Article 36 of the Vienna Convention on Consular Relations.
Salve admitted that while India's ambitious call for an annulment of Jadhav's death sentence was not met, the court had been categorical in its verdict that Pakistan must do everything to make the Vienna Convention a living reality.
India moved the ICJ on May 8, 2017, for the "egregious violation" of the provisions of the Vienna Convention by Pakistan by repeatedly denying New Delhi consular access to Jadhav.
Salve said he had a "degree of personal satisfaction" that he did not resort to the kind of adjectives used by Pakistan in trying to accuse India of state-sponsored terrorism during the course of the hearings, except to describe them as "unfortunate".
"I had told the court that my upbringing and India's traditions do not allow me to reply in that language," he said, adding that the vindication came in the form of the ICJ rejecting Pakistan's allegations against India of abuse of process.
While Pakistan has claimed that Jadhav was taken into custody after he illegally entered Balochistan from Iran in March 2016, India says that he was abducted from Iran where he had business interests in Chabahar and maintains his innocence.
The verdict in the high-profile case comes nearly five months after the bench had reserved its decision on February 21 after hearing oral submissions by India and Pakistan. The proceedings of the case took two years and two months to complete.