Promising to help Sarabjit Singh, Pakistani human rights campaigner Ansar Burney on Tuesday said he will seek pardon from the relatives of those killed in bomb blasts allegedly involving the Indian prisoner.

Burney, who met Home Minister Shivraj Patil and Foreign Secretary Shiv Shankar Menon in Delhi, said he would also take up the case of another Indian national languishing in a Pakistani jail for 28 years.

"A woman met me recently saying her father was in Pakistani jail for 28 years serving life sentence. It is more serious than Sarabjit," said the former Pakistan minister who helped secure release of Kashmir Singh about two months back.

On Sarabjit, who is on death row in connection with 18-year-old blasts, Burney said he will return to Pakistan and "request the families of the 14 victims to pardon him. I will request them that they should pardon him if saving the life of one person can help building brotherhood between the two countries."

Sarabjit was to be hanged on April 1, but it was postponed by a month after India made an appeal for clemency on "humanitarian grounds".

Burney, who met Sarabjit's family in Punjab last week, said he had got a copy of the FIR on his disappearance and he has forwarded it to the Punjab government in Pakistan for verification.

"This is an 18-year-old FIR. We have to cross check its authenticity," he said as he rubbished reports that Sarabjit crossed into Pakistan in an inebriated state.

On reports that a witness had made a statement against Sarabjit under pressure, the lawyer-activist said, "If that is the case, then his death sentence should be changed to life sentence."