Cutting all economic and diplomatic ties, putting sanctions and blocking ships headed to or from there passing through the red sea would indicate he means it.
If the arab leaders had made a stance, the genocide would have ended in November and Israel would be back in 1967 borders by end of next year.
Reports in Arabic-language media suggest that there have been several meetings between Saudi Arabia's Crown Prince Mohammed bin Salman and Israeli officials over the last two years, with at least one of them taking place in Eilat in 2015 and another on the sidelines of the Arab summit in Jordan in March 2017. It has also been reported that Saudi and Israeli officers have been regularly meeting in a joint war room serving as a coordination center for Jordan, Saudi Arabia, and the United States.
After the Arab Spring, Israel views the Saudi government as "guarantor of stability", according to the New York Times. In 2011, Israel approved a German sale of 200 Leopard tanks to Saudi Arabia.[12] The approval came from Uzi Arad, the national security advisor to Benjamin Netanyahu.
The Times has reported that Saudi Arabia has tested the ability to stand down their air defenses to allow an Israeli strike on Iran to pass through their airspace.[22] Both nations have denied this.[23][24]
In November 2018, Netanyahu publicly defended Saudi Crown Prince Mohammad bin Salman in the wake of the killing of Jamal Khashoggi, stating "it is very important for the stability of the region and the world that Saudi Arabia remain stable", and privately urged the U.S. administration to maintain its strong security relationship with Saudi Arabia.[31]
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They egg around but work together closely militarily and in intelligence. And Saudia Arabia could exert control over the Red Sea. Finally Saudi Arabia actively supports Israel militarily, like by shooting down missiles heading to Israel from Yemen.