India's Supreme Court has said that it will not intervene in the case of an Indian man accused of conspiring to kill a Sikh separatist on US soil.
US prosecutors have charged Nikhil Gupta with trying to hire a hitman to assassinate Gurpatwant Singh Pannun.
Mr Gupta is in jail in Prague, and his lawyer has said that the process to extradite him to the US has started.
"It is for the [Indian] government to take action," the Supreme Court said, rejecting the plea.
The petition, filed by an anonymous relative of Mr Gupta, had asked the Indian Supreme Court to aid his release and help him get a fair trial. His lawyer had also alleged that Mr Gupta was detained illegally.
"Looking at the principles of public international law and sovereignty and comity of courts we do not think any of the prayers can be granted," Justice Sanjay Khanna, one of the two judges on the bench, said, calling it a "sensitive matter". A copy of the order will be released later on Thursday.
Earlier, the Czech Republic's ministry of justice had told The Indian Express newspaper that Indian courts had "no jurisdiction" in Mr Gupta's case.
Mr Gupta made headlines in November when US prosecutors charged him with a plot to kill at least four Sikh separatists in North America, including Mr Pannun.
They said that Mr Gupta promised to pay $100,000 (£79,000) in cash to a hitman to assassinate Mr Pannun, a dual US-Canadian citizen, in New York. But the hitman was actually an undercover federal agent, prosecutors said.
Mr Gupta was allegedly directed by an Indian government official who was not named or charged in the indictment.
The charges against Mr Gupta carry up to 20 years in prison.
India has designated Mr Pannun a terrorist, an allegation he denies, claiming to be an activist who believes in the Khalistan movement for a separate Sikh homeland.
The petition in India claimed that Mr Gupta was arrested by "self-claimed" US federal agents and has not yet been given a fair trial. It also alleged that he was lodged in solitary confinement and was forced to eat beef and pork, which went against his religious beliefs.
The Supreme Court judges said that under international law, Mr Gupta would be entitled to consular assistance from India. But senior advocate C Aryama Sundaram, who represented Mr Gupta's relative, said that he had been provided consular access only before the extradition order and that his client needed "some cooperation" from India's foreign ministry.
The court then said that he was free to approach the Indian government.
The charges against Mr Gupta came months after Canada's Prime Minister Justin Trudeau said his country was looking at "credible allegations potentially linking" Indian government agents to the murder of a Sikh separatist leader in British Columbia. India has rejected the allegations and called them "absurd".
India has, however, said it will look into any evidence provided on its alleged links to the assassination plot in the US.
"If a citizen of ours has done anything good or bad, we are ready to look into it. Our commitment is to the rule of law," Prime Minister Narendra Modi told the Financial Times last month.
