Saudi Arabia's King Salman said on Sunday that he "absolutely rejects" any measures that impact on Syrian sovereignty over the Golan Heights.
Addressing an Arab League summit in Tunis, he also reiterated Saudi Arabia's position supporting the establishment of a Palestinian state in the West Bank and the Gaza Strip, with East Jerusalem as its capital.
“The Palestinian issue will top the agenda of the Kingdom of Saudi Arabia until the Palestinian people gets their legitimate rights, on top of which its establishment of its country in correspondence to the 1967 borders,” King Salman said.
The Saudi King's comments were echoed by leaders of the United Nations and Tunisia, who also called for a two-state solution and Syrian sovereignty over the Golan.
Tunisian President Beji Caid Essebsi also said on Sunday that the summit needed to send a message on the importance of establishing a Palestinian state.
Regional and international stability should come through "a just and comprehensive settlement that includes the rights of the Palestinian people and leads to the establishment of a Palestinian state with Jerusalem as its capital," Mr Essebsi said.
United Nations Secretary-General Antonio Guterres also called for a two-state solution.
King Salman added the importance of trying to find a political solution to Yemen, which has placed 14 million on the brink of starvation.
“On Yemen, we stress here our support for the United Nations' efforts to reach a political solution to the crisis in Yemen and we urge the international community to work hard against the Houthi militias and against Iranian intervention,” he said.
He also stressed that Iran’s interference in Arab affairs is “a flagrant violation of international principles and the international community should assume the responsibility to face these policies that Iran uses to support terrorism”.
US President Donald Trump signed a proclamation last week recognising the Golan Heights as Israeli, less than a year after recognising Jerusalem as Israel's capital.
“We need to stress our categorical rejection to all procedures that strain Syrian sovereignty to the Golan heights and we stress the importance of sorting the Syrian crisis,” he said.
Mr Guterres also said any resolution in the Syrian conflict must guarantee the territorial integrity of Syria over the Golan Heights.
The Arab League summit in Tunisia is expected to see its 22 nations unite against destabilising unrest in the region and provide a window on members' views on the long-standing Palestinian-Israeli conflict weeks before the US unveils its so-called "deal of the century" to resolve the issue.
Several regional leaders have been briefed on the long-awaited US peace plan that Jared Kushner, President Donald Trump’s senior adviser and son-in-law, has been working on.
Earlier this year, Mr Kushner visited several Arab countries to give them details on the economic components of the deal, which he promised to unveil after Israel's elections on April 9.
Reactions have mostly been muted but several Arab leaders have hinted at a failure to address the Palestinians' main concerns. Others have cautioned against rejecting a deal that has not yet been fully revealed.
Although they differ in their stance on the peace deal, Arab leaders are expected to unite in opposition to the Trump administration's decision to recognise Israel's annexation of the Golan Heights captured from Syria in the 1967 War.
Gebran Bassil, Lebanon's foreign minister, said support is increasing among the delegates for a proposal to declare the move a breach of the UN charter, which prohibits acquisition of territory by force.
Summit spokesman Mahmoud Al Khmeiry said leaders would repeat an offer of peace with Israel in exchange for withdrawal from occupied Arab lands and would reject any initiative not in line with UN resolutions.
Arab officials also agreed to Lebanon’s right to the Shebaa Farms, a small strip of disputed land next to the Golan Heights.
Unrest in Algeria and Sudan will also be on the agenda and the civil war in Yemen, now in its fifth year, will feature prominently during the discussions.
Ibrahim Al Assaf, foreign minister of Saudi Arabia, said on Friday that Iran remained the biggest threat to the region.
The Tunis summit will be the first time the rulers of Saudi Arabia and Qatar attend the same gathering since the dispute between Riyadh and its allies and Doha in 2017. Saudi Arabia and its allies accuse Qatar of supporting terrorism and cosying up to Iran, charges Doha denies.
The leaders of Sudan and Algeria are not expected to attend because of anti-government protests in their countries.
Abdelaziz Bouteflika, Algeria's ailing 82-year-old president who has ruled for 20 years, and Sudanese president Omar Al Bashir, in power for three decades and wanted by international prosecutors for alleged war crimes in his country's Darfur region, are both facing calls to step down.
The UN's top diplomat, Mr Guterres welcomed efforts for a peaceful and democratic transition in wake of protests against Mr Bouteflika.
The League has said there is still no consensus on reinstating Syria's membership, which was suspended in 2011 over President Bashar Al Assad's crackdown on protesters at the start of its civil war.