Saudi Arabia's Crown Prince Mohammed bin Salman has "ordered the immediate release" during his high-profile visit to Islamabad.
In a post on Twitter, Pakistan's Information Minister Fawad Chaudhry said the crown prince took the call following a request by Pakistani Prime Minister Imran Khan.
Prince Mohammed is in Pakistan at the beginning of an Asian tour, which will include India and China.
This comes as Saudi Arabia on Sunday signed investment agreements with Pakistan worth $20 billion.
Saudi Arabia has yet to comment on the Pakistani announcement of a prisoner release.

US Epstein files release highlights Clinton, makes scant reference to Trump
Bangladesh holds state funeral for slain youth leader amid tight security
US hits ISIS in Syria with large retaliatory strikes, officials say
Pakistan court hands Imran Khan, wife 17-year jail terms in another graft case
Seven elephants killed in India train accident
Israeli attack on school shelter in Gaza City kills 5 Palestinians
Nine injured in attack in Taipei, media reports
Putin offers no compromise on Ukraine, says EU 'robbery' failed
