The phone call by Mathai came as a special Air India plane is set to leave for Lahore shortly to bring back the body.
"Foreign Secretary spoke to his Pakistani counterpart and asked him to speed up the process of handing over Sarabjit's body," official sources said.
Asked what was Pakistani response, they said they will try.
49-year-old Sarabjit, who was brutally attacked in a high-security Lahore jail by fellow inmates on Friday, succumbed to his injuries early today.
He was convicted of alleged involvement in a string of bomb attacks in Pakistan's Punjab province that killed 14 people in 1990 and spent about 22 years in Pakistani prisons. Sarabjit's family has said his was a case of mistaken identity.