"The morning bulletin was not very encouraging, the parameters were falling. Just keeping our fingers crossed. Frankly hoping for the best to happen. I hope that he would be able to recover," he told reporters outside Parliament House.
Doctors treating the death row convict have said that Sarabjit's condition continues to be serious but he has not been declared brain dead.
Doctors had earlier said his chances of survival were "slim" due to extensive head injuries.
Sarabjit, 49, sustained several injuries, including a skull fracture, when six prisoners attacked him in Kot Lakhpat Jail on Friday. He was hit on the head with bricks and his neck and torso cut with sharp weapons.
He was convicted of alleged involvement in a string of bomb attacks in Punjab province that killed 14 people in 1990. His mercy petitions were rejected by the courts and former President Pervez Musharraf.
The outgoing Pakistan People's Party-led government put off Sarabjit's execution for an indefinite period in 2008.
Sarabjit's family says he is a victim of mistaken identity and had inadvertently strayed across the border in an inebriated state.