"Requesting the people of Pakistan to support me to help free Sarabjit, who has been in prison since 30 yrs. Please. Allah ka vasta (for god's sake)," Salman tweeted.
"Request the awam (people) of Pakistan, members of the press, Govt of Pakistan, President (Asif Ali Zardari) Zardari, a humble request. It would be the most amazing gesture to send Sarabjit back to his family after 30 years. Hope you support me like it's your own cause," he added.
Hours after reports emerged that Pakistan was to free Sarabjit, the officials clarified that another Indian prisoner named Surjeet Singh, who has been in jail for three decades, would be released instead. The change of stance created a stir across India.
The actor was upset after he saw Sarabjit's family in dispair.
"I saw a picture of Sarabjit's sister, it killed me. Felt real sad for her. Help me, help her," he tweeted further.
External Affairs Minister S M Krishna said he hopes that Pakistan will seriously 'ponder and consider' and release death row convict Sarabjit Singh too.
"I am happy that Surjeet Singh is being released and I hope that Pakistan will also seriously ponder and consider and release Sarabjit Singh also," Krishna said.
In New Delhi on Thursday, Dalbir Kaur, the sister of Sarabjit Singh, demonstrated at Jantar Mantar and said Pakistan should release her brother.
Dalbir also met SM Krishna over the issue of his brothers' release from a Pakistan prison.
Initial reports of Sarabjit's release had triggered celebrations in his family in India but later the Pakistan authorities said it was Surjeet Singh and not Sarabjit Singh who would be released.
Claiming that his brother charged with terrorism and spying is 'innocent' , Dalbir said Pakistan President Asif Ali Zardari should rethink his decision and release him.
Dalbir said she will continue to fight for Sarabjit's release from Pakistan prison.
Pakistani human rights activist Ansar Burney told an Indian TV channel that the sudden change in the Presidential stance might be under the pressure of the mullahs.
Sarabjit Singh has been languishing in a Pakistani jail for over 20 years after a Pakistani anti-terrorist court awarded him the death sentence in 1991.
He had been convicted of involvement in a string of bombings in Punjab in 1990 that killed 14 people.
The developments came two months after Pakistani microbiologist Khalil Chishty, accused in a 1992 murder case, walked free from an Indian prison after being granted interim bail by the Supreme Court.