Saudi Arabia's de facto ruler told Palestinian president Mahmud Abbas he was working to prevent "an expansion" of conflict after the surprise Hamas attack on Israel, Saudi state media said early Tuesday.

Crown Prince Mohammed bin Salman also told Abbas the Gulf kingdom continued "to stand by the Palestinian people to achieve their legitimate rights to a decent life, achieve their hopes and aspirations, and achieve just and lasting peace," the official Saudi Press Agency reported.

Reeling from the Palestinian Islamist group's unprecedented ground, air and sea attacks, Israel has counted 800 dead and launched a withering barrage of strikes on Gaza that have raised the death toll there to 687.

The spiralling violence kicked off amid speculation that Saudi Arabia, which has never recognised Israel, would agree to normalise ties as part of a deal in which it would obtain security guarantees from the United States as well as assistance developing a civilian nuclear programme.

However Prince Mohammed told Fox News last month that the Palestinian issue was "very important" for Saudi Arabia, home to the holiest sites in Islam in Mecca and Medina.

"We need to solve that part. We need to ease the life of the Palestinians," Prince Mohammed said.

Analysts say any progress towards normalisation has now been dealt a heavy blow by the ongoing fighting.

Prince Mohammed has also spoken about the crisis by phone with Egyptian President Abdel Fattah al-Sisi and Jordan's King Abdullah II, SPA reported.