The leaders of Turkiye and Iran called on Thursday for unity in Syria at a summit of eight Muslim-majority countries after the ouster of Syria's president Bashar al-Assad.
Turkiye historically backed Assad's opponents, while Iran supported his rule.
The gathering of the D-8 Organisation for Economic Cooperation, also known as the Developing-8, was being held against a backdrop of regional turmoil including the conflict in Gaza, a fragile ceasefire in Lebanon and unrest in Syria.
In a speech at the summit, Turkish President Recep Tayyip Erdogan, called for reconciliation in Syria and the restoration of the country's "territorial integrity and unity".
He also voiced hope for "the establishment of a Syria free of terrorism", where "all religious sects and ethnic groups live side by side in peace".
Iranian President Masoud Pezeshkian also called for "the participation of all (Syrian) groups in the future government... as well as respect for different beliefs and religions".
He added that "for more than 14 months, the Middle East region, in particular Gaza and southern Lebanon, and now... Syria, has been the target of massive attacks" by Israel.
"It is our religious, legal and human duty to prevent further harm" to those suffering in the conflict zones, he said.
Pezeshkian is the first Iranian president to visit Egypt since Mahmoud Ahmadinejad in 2013.
Relations between Egypt and Iran have been strained for decades, but diplomatic contacts have intensified since Cairo became a mediator in the war in Gaza.
Iran's Foreign Minister Abbas Araghchi visited Egypt in October, while his Egyptian counterpart Badr Abdelatty travelled to Tehran in July to attend Pezeshkian's inauguration.
Palestinian president Mahmud Abbas, speaking at a special session on Gaza and Lebanon, said the international community should adopt "a single standard of justice" and ensure Israel "is held accountable and punished for violations of international law" in Gaza, Lebanon and Syria.
Abbas called for the adoption of a political plan he presented at a November summit in Riyadh, which includes a ceasefire, Israel's complete withdrawal from Gaza and full UN membership for Palestine.
Iran's president expressed support for any agreement backed by all Palestinian factions.
"The right to self-determination of the Palestinian people must be respected," said Pezeshkian.
He called on the international community to pressure Israel to implement a ceasefire in Gaza, end attacks on Lebanon and Syria and facilitate the delivery of humanitarian aid to the Gaza Strip.
The Cairo summit also hosted a meeting between Bangladesh's interim leader Muhammad Yunus and Pakistan's Prime Minister Shehbaz Sharif.
Bangladesh's interim leader Muhammad Yunus said he had "agreed to strengthen relations" with Pakistan.
Established in 1997, the D-8 aims to foster cooperation among member states, spanning regions from Southeast Asia to Africa.
The organisation includes Egypt, Turkey, Iran, Nigeria, Pakistan, Bangladesh, Indonesia and Malaysia as member states.
Iranian President Masoud Pezeshkian, Egyptian President Abdel Fattah El-Sisi, Turkish President Recep Tayyip Erdogan pose with other leaders for a group photo during the D-8 summit in Cairo on Thursday
Turkish President Tayyip Erdogan meets with Iranian President Masoud Pezeshkian on the sidelines of D-8 summit in Cairo, Thursday