Arab and Muslim leaders have demanded that Israel withdraw from occupied Palestinian territories as a precondition for regional peace, while denouncing "shocking" Israeli crimes in war-ravaged Gaza.

A summit meeting in the Saudi capital Riyadh on Monday gave the Arab League and the Organization of Islamic Cooperation's 57 nations a chance to speak with one voice on turmoil engulfing the region, more than a year into the Israel-Hamas war in the Gaza Strip.