The two countries signed a raft of investment deals worth $20 billion (over AED 73 billion) on Sunday in a bid to boost Pakistan's fragile economy.
It comes as part of Saudi Crown Prince Mohammed bin Salman's high-profile three-country Asian tour.
Prime Minister Imran Khan thanked their long-time ally for its support. "Pakistan and Saudi Arabia are now taking this relationship to a level which (they) never had before."
The Crown Prince also expressed confidence in Pakistan's economy.
Khan also drove the Saudi Crown Prince to the PM house, just as he had done while welcoming His Highness Sheikh Mohamed bin Zayed Al Nahyan, Crown Prince of Abu Dhabi and Deputy Supreme Commander of the UAE Armed Forces, this year.

Trump says deal reached to disarm Hamas, Israeli support for plan remains uncertain
Kuwait says Iranian attack hits Chinese company building, kills one
Japan quake snarls auto and chip supply chains as toll hits 34
Death toll rises to at least 34 after blast at Pakistan coal mine complex
