Arab and Muslim leaders have begun arriving in Saudi Arabia for a summit scheduled for Monday that will focus on Israel's wars in Gaza and Lebanon, Saudi state media said.
The Saudi foreign ministry announced the summit in late October, during the first meeting of an "international alliance" pushing for a two-state solution to the Israeli-Palestinian conflict.
Attendees will "discuss the continued Israeli aggression on the Palestinian territories and the Lebanese Republic, and the current developments in the region," the official Saudi Press Agency said on Sunday.
It comes one year after a similar gathering in Riyadh of the Cairo-based Arab League and the Jeddah-based Organization of Islamic Cooperation (OIC) during which leaders condemned Israeli forces' actions in Gaza as "barbaric".
The Saudi state-affiliated Al-Ekhbariya news channel broadcast footage on Sunday of Nigerian President Bola Tinubu and Lebanese Prime Minister Najib Mikati landing in Riyadh.
Pakistani Prime Minister Shehbaz Sharif was also scheduled to attend, the Pakistani foreign ministry said last week, adding that he planned to call for "an immediate end to the genocide in Gaza" and the "immediate cessation of the ongoing Israeli adventurism in the region".
In a phone call with Saudi Crown Prince Mohammed bin Salman, Iran's President Masoud Pezeshkian said he would not take part in the meeting due to pressing "executive matters", according to a government statement.
Pezeshkian noted that Iran's First Vice President Mohammad Reza Aref will attend instead, expressing confidence that the meeting "will have effective and tangible results in ending the crimes of the Zionist regime and the war and bloodshed in Gaza and Lebanon".
The 57-member OIC and 22-member Arab League include countries which recognize Israel and those firmly opposed to its regional integration.
Last year's summit in Riyadh saw disagreement on measures like severing economic and diplomatic ties with Israel and disrupting its oil supplies.
The war in Gaza erupted with Hamas's unprecedented attack on southern Israel on 7 October last year, which resulted in 1,206 deaths, mostly civilians, according to an AFP tally of Israeli official figures.
Israel's retaliatory campaign has killed more than 43,600 people in Gaza, most of them civilians, according to data from the Hamas-run territory's health ministry that the United Nations considers reliable.
Lebanon-based Hezbollah, which like Hamas is backed by Iran, began firing on Israel after the 7 October attack.
The regular cross-border exchanges escalated in late September when Israel intensified its air strikes before sending ground troops into southern Lebanon against Hezbollah.