Humza Yousaf has urged the prime minister to ask the Indian government to release a Scottish Sikh blogger who has been in jail since 2017.
In a letter, the first minister said Jagtar Singh Johal had been wrongfully imprisoned, and called on Rishi Sunak to take a “direct approach”.
Mr Singh Johal, from Dumbarton, was in Punjab for his wedding when he was arrested over an alleged murder conspiracy.
He faces a possible death penalty.
His family say he has been tortured, including through electric shocks, before being made to sign a blank confession document.
These allegations have been denied by the Indian authorities.
In Scotland, Mr Johal was an active blogger, highlighting historical human rights abuses and atrocities against Sikhs in the Punjab region.
He has been detained in a series of Indian prisons, accused of funding the purchase of weapons used to assassinate a number of right-wing Hindu religious and political leaders in the Punjab.
He denies the charges against him and says his arrest and trial are politically-motivated.
Mr Yousaf met Gurpreet Singh Johal, the brother of Jagtar Singh Johal, earlier this month and vowed to keep lobbying for his release.
In his letter to Mr Sunak, the first minister said: “Jagtar has now been imprisoned in India for over 2,000 days.
“In May 2022, the UN Working Group on Arbitrary Detention concluded that Jagtar Singh Johal had been arbitrarily detained and his detention breached international human rights law.
“The clear recommendation of the report was that Jagtar Singh Johal should be immediately released. Yet Jagtar remains in prison.
“I am therefore writing to ask that you make a direct approach to the government of India to ask for Jagtar’s immediate release in line with the UN Working Group’s unequivocal recommendation.
“This would give the family the reassurance of knowing that the UK government is prioritising the protection of a citizen who has been wrongfully imprisoned.”
The Foreign Office said it had raised its concerns, including Mr Johal’s allegations of torture, with the Indian government on more than 100 occasions and would continue to do so.
It said consular staff visit him regularly to check on his welfare and did so most recently on 1 May. They also continue to attend relevant court hearings in an observer capacity.
A spokesman said the Foreign Secretary most recently discussed Mr Johal’s case with the Indian external affairs minister in New Delhi on 1 March.