President Xi Jinping was meeting Arab leaders in Riyadh on Friday on day three of his visit to Saudi Arabia for summits he has described as "milestone events".

Friday's agenda was expected to include a summit with the six-member Gulf Cooperation Council (GCC) as well as a broader China-Arab summit.

"China looks forward to working with Saudi Arabia and Arab countries to make the two summits milestone events in the history of China-Arab relations and China-GCC relations," Xi said in remarks carried by CCTV.

Meanwhile, China and Saudi Arabia reaffirmed the significance of stability in global oil markets and the Saudi role in that, a joint statement said on Friday.

"The People's Republic of China welcomed the Kingdom’s role as a supporter of the balance and stability in the world oil markets, and as reliable major exporter of crude oil to China," the statement said.

On Thursday, Xi met with King Salman and Saudi Arabia's de facto ruler, Crown Prince Mohammed bin Salman, announcing deals from hydrogen energy to housing.

The two countries also agreed to jointly advance the China-Saudi Arabia comprehensive strategic partnership.

Saudi state TV al-Ekhbariya reported on Friday that Xi has invited King Salman to visit China. (Agencies)