Former Pakistan prime minister Imran Khan has 15% vision left in his right eye after prison authorities failed to take action, his lawyers have told Pakistan's supreme court.

Axar.az informs, citing BBC, his lawyer Salman Safdar, who was permitted to visit his client in prison this week, said the former cricketer began experiencing blurred and hazy vision three to four months ago.

But, despite telling the jail superintendent, no action was taken beyond giving him eye drops, Safdar said.

Pakistan's authorities previously confirmed Khan had a 20-minute medical procedure on 24 January at Islamabad's PIMS hospital, when minister Ata Tarar said Khan was "fine and healthy".