Saudi Arabia's King Salman met with China's premier on Friday, a day after the two nations signed a memorandum of understanding on investment cooperation valued at $65 billion.
The deals included a memorandum of understanding (MoU) between giant state oil firm Saudi Aramco [IPO-ARMO.SE] and China North Industries Group Corp (Norinco) [CNIGC.UL], to look into building refining and chemical plants in China.
The landmark agreement aims to boost joint efforts in fields including energy, investment, finance, culture and aerospace, part of Saudi Arabia's drive to develop a growth strategy less dependent on oil.
Saudi Basic Industries Corp (SABIC) and Sinopec, which already jointly run a chemical complex in Tinajin, also agreed to develop petrochemical projects in both China and Saudi Arabia.
Beijing meanwhile is rolling out a massive trade and investment initiative across Central Asia and the Middle East called "One Belt, One Road" that sees the desert kingdom as a regional linchpin.
Despite the eye-catching sum noted in the memo, the actual value of such commitments is usually much smaller once projects begin.
Saudi Arabia is China's biggest supplier of crude oil and the kingdom's state-owned oil producer, Aramco, is a partner with state-owned China Petroleum & Chemical Corp. The two operate a refinery in Fujian province along with other Chinese projects.
The signing of the agreement, which involves 35 separate projects, followed talks Thursday between Salman and President Xi Jinping, during which the Chinese leader said results of their burgeoning cooperation had already "surpassed our expectations."
Security ties between the two have also grown significantly, with the Saudi air force deploying Chinese unmanned attack drones and the two militaries holding joint counter-terrorism exercises in western China.Chinese navy vessels have also visited the Saudi port of Jeddah as part of increasingly active maneuvers in the Gulf of Aden.
Saudi Arabia's octogenarian monarch, who has overseen the launch of an ambitious economic reform plan since his accession two years ago, is on a month-long Asian tour. Accompanied by a 1,500-strong retinue of businessmen, princes and support staff in close to a dozen aircraft, he has already visited Japan, Indonesia, Malaysia and Brunei, and travels next to the Indian Ocean island nation of the Maldives.