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.
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