On visit to Egypt, Adel Al-Jubeir calls on Iran to "stop supporting terrorism."
"None of us, Russia, the United States, coalition, and regional states, wants to see a collapse of the government and political institutions in Damascus."
King Salman has used summits with leaders of all five Gulf Arab states, Jordan, Egypt and Turkey over the past 10 days to reinforce the need for unity.
Diplomats claim they are "very conscious that philanthropic and humanitarian assistance does not fall into the hands of extremist elements.”
“The changes that the Middle East has experienced in recent years have created a set of joint interests between the two countries,” said Dr. Michal Yaari, an expert on Saudi foreign policy.
Saudi Arabia's elderly monarch was admitted to hospital on Wednesday for medical tests, state media said.
"If Iran wants to be part of the solution, it has to pull its forces from Syria. The same applies elsewhere, whether in Yemen or Iraq," Saudi FM says.
Shi'ite Muslim Iran and Sunni Saudi Arabia are enmeshed in a struggle for influence across the Middle East and back opposing sides in conflicts across the region.
<i>Wall Street Journal</i> cites Arab, Western diplomats as saying that rebels to receive shoulder-fired missiles, anti-tank weapons.