King Salman named the current Arab League Summit the "Jerusalem Summit" to remind everyone around the world that Palestine is engraved in the conscience of the Arab people.
Saudi Arabia is pushing for a tough, unified stance against Iran at the annual gathering of the 22-member Arab League.
The two regional titans, locked in proxy wars in Syria and in Saudi Arabia's southern neighbour Yemen, back opposing parties in Iraq and Lebanon.
Saudi Arabia, the United Arab Emirates, Bahrain and Egypt severed diplomatic and transport ties with Qatar in June 2017, accusing it of supporting terrorism.
Summits of the Arab League, established in 1945, rarely result in action.
Syria has been suspended from the organization for seven years over Assad's crackdown on protesters.
He said Al Houthi militants in Yemen, backed by Iran, had fired 116 missiles at the kingdom since Saudi Arabia intervened to stem Iranian expansionsism and restore the internationally-recognised government of Abd Rabbo Mansour Hadi.
Commonwealth Games 2018: WATCH shocking moment Callum Hawkins COLLAPSES in marathon
The Scotsman got back on his feet and continued racing before collapsing again, this time hitting his head on a roadside barrier. Hawkins, who was fourth at the World Championships a year ago , was reported one hour after the race to be conscious.
Iran has always been a supporter of Syrian President Bashar Assad and backs Lebanon's Hezbollah, whose fighters are deployed in Syria alongside regime forces.
The ongoing Qatar-Gulf crisis is also expected to take center stage during the summit.
Its foreign ministry tweeted support for "operations against specific military targets used by Syrian regime in its chemical attacks".
Gulf Arab states have made great relief donations to Syria but have not officially offered asylum to Syrians.
Seven years into a war that has killed hundreds of thousands of people lives, Saudi Arabia and Iran now agree that the country's future can not be decided exclusively by the Syrian government, whose troops have regained the upper hand with military support from Russian Federation.
Saudi Arabia's King Salman opening the summit criticised US President Donald Trump's decision to transfer the US embassy in Israel from Tel Aviv to Jerusalem.
Sheikh Tamim returned to Doha on Saturday from a USA trip where he met President Donald Trump, who had publicly sided with the Saudis and Emiratis early in the crisis, but is now pushing for a resolution to restore Gulf Arab unity and maintain a united front against Iran.