Human Rights Watch has urged Pakistan not to execute a mentally ill man who is scheduled to be hanged on Tuesday.
The charity said Khizar Hayat, who was sentenced to death 12 years ago for killing a colleague, suffers from severe paranoid schizophrenia.
Authorities in Pakistan are about to resume executions after a break for the Muslim holy month of Ramadan.
According to Human Rights Watch (HRW), the country has executed 176 people since lifting a moratorium in December.
Phelim Kine, deputy Asia director at HRW, said executing people with mental illnesses was “a barbarous affront to decency” that “serves no criminal justice purpose”.
“Pakistan’s president should immediately commute Khizar Hayat’s execution and prevent a ghastly infringement of basic rights,” Mr Kine said.
“The Pakistani government should take this opportunity to reaffirm its human rights commitments and explicitly reject the odious practice of executing people with psychosocial disabilities.”
The UN Commission on Human Rights adopted resolutions in 1999 and 2000 urging countries not to impose the death penalty “on a person suffering from any form of mental disorder”.
Mr Hayat, a former policeman, was arrested in 2001 for allegedly killing a colleague and in 2003 he was sentenced to death.
In 2008, he was diagnosed with paranoid schizophrenia and he has been taking antipsychotic medication since.
According to his lawyers, by 2012 Mr Hayat had become so delusional that he was moved to the prison hospital where he has spent the past five years.
Pakistan suspended executions for seven years until December 2014, when they were resumed in the wake of the Peshawar school massacre.
There are more than 8,000 people on death row in the country, according to HRW. About 1,000 have lost their appeals and had clemency petitions rejected.
Supporters of the death penalty in Pakistan argue that fast-track executions are needed to rein in militant attacks.