Saudi Arabia's de facto ruler on Monday called on Israel to respect Iran's sovereignty and refrain from attacking Iranian soil, highlighting warming ties between the Middle East rivals.

Crown Prince Mohammed bin Salman told a summit of Arab and Muslim leaders that the international community should oblige Israel "to respect the sovereignty of the sisterly Islamic Republic of Iran and not to violate its lands".

Opening the summit, he said the international community must "immediately halt the Israeli actions against our brothers in Palestine and Lebanon", condemning Israel's campaign in Gaza as "genocide".

"(Saudi Arabia) affirms its support for the brothers in Palestine and Lebanon to overcome the disastrous humanitarian consequences of the ongoing Israeli aggression," he said.

A draft resolution for the summit stresses "firm support" for "national rights" for the Palestinian people, "foremost among which is their right to freedom and to an independent, sovereign state".

Just hours earlier, newly appointed Israeli Foreign Minister Gideon Saar said it was not "realistic" to establish a Palestinian state, dismissing it as a "Hamas state".

"I don't think this position is realistic today and we must be realistic," Saar said in response to a question during an appearance in Jerusalem.

The Saudi foreign ministry announced plans for the summit in late October during a meeting, also in Riyadh, of a new "international alliance" to press for the establishment of a Palestinian state.

It comes one year after a similar gathering in Riyadh of the Cairo-based Arab League and the Jeddah-based Organisation of Islamic Cooperation during which leaders condemned Israeli forces' actions in Gaza as "barbaric". (AFP)