Egyptian President Mohamed Morsi has said it is an "ethical duty" to support the Syrian people against the "oppressive regime" in Damascus.
His speech at the Non-Aligned Movement summit in Tehran on Thursday prompted a walkout by the Syrians.
"Our solidarity with the struggle of the Syrian people against an oppressive regime that has lost its legitimacy is an ethical duty as it is a political and strategic necessity," Morsi said.
"We all have to announce our full solidarity with the struggle of those seeking freedom and justice in Syria, and translate this sympathy into a clear political vision that supports a peaceful transition to a democratic system of rule that reflects the demands of the Syrian people for freedom."
Al Jazeera's Imran Khan, reporting from the summit, said: "Morsi's comments have caused an unease feeling, especially for the Iranians who are close to Syria."
PHOTO CAPTION
Egypt's President Mohamed Mursi (front R) arrives in Mehrabad airport in Tehran ahead of the 16th summit of the Non-Aligned Movement, August 30, 2012.
Al-Jazeera