The Pakistan government will continue to facilitate the "early completion of all formalities and hand over the mortal remains of the prisoner to the Indian High Commission at the earliest possible", said a statement from the Foreign Office.
The body of 49-year-old Sarabjit was moved to the mortuary of JinnahHospital in Lahore shortly after he died of cardiac arrest at around 1 am. (1:30 am IST)
He had been comatose since Friday, when he was attacked by six other prisoners within his barrack at Kot Lakhpat Jail.
The Foreign Office said the Pakistan government had been providing "all assistance to the family of Sarabjit Singh as well as to the Indian authorities since the occurrence of this unfortunate incident".
The statement said Sarabjit had died of cardiac arrest despite being "provided the best treatment available" and the staff of JinnahHospital working round the clock to save his life.
Pakistan's Foreign Secretary Jalil Abbas Jilani was quoted by the media as saying that the body would be "expeditiously" handed over to India after completing necessary formalities.
Official sources in Islamabad and Lahore said an autopsy and other formalities will have to be completed before handing over the body. A medical board will oversee the autopsy.
The Indian High Commission was in touch with both the federal and Punjab governments on the issue, the sources said.
Indian High Commissioner Sharat Sabharwal, who is in Lahore, is expected to meet Punjab Caretaker Chief Minister Najam Sethi later in the day.
Sarabjit was convicted of alleged involvement in a string of bomb attacks in Punjab province that killed 14 people in 1990 and spent about 22 years in Pakistani prisons.
His family says he was the victim of mistaken identity and had inadvertently strayed across the border in an inebriated state.
Sarabjit's mercy petitions were rejected by the courts and former President Pervez Musharraf.
The previous Pakistan People's Party-led government put off Sarabjit's execution for an indefinite period in 2008.
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