A memorandum of understanding has been reportedly signed to help the kingdom develop its own defense industries.
The Russian Deputy Prime Minister Dmitry Rogozin has already said Riyadh was showing interest in buying Russian missile systems.
“There is some interest, of course. Talks on S-400 are in progress, but there are no final decisions yet,” he said today, adding that confidential negotiations on military-technical cooperation were being held.
The S-400 is Russia’s most advanced long-range anti-aircraft missile system and can carry three types of warheads designed to destroy targets including ballistic and cruise missiles.
The system is able to track and engage up to 300 targets to an altitude of 27 kilometers at the same time.
The deal is a potential coup for Russia. Saudi Arabia has traditionally purchased defense equipment from the United States.
In June, the kingdom signed its biggest ever defense contract to buy American Terminal High Altitude Area Defense (THAAD) defense systems, guided missile frigates, military planes, and howitzers.
Earlier this year, Turkey signed a deal to buy the S-400 missile system from Russia with deliveries reportedly to start within two years.