An Iranian man walks by a mural on the wall of the former U.S. embassy in the Iranian capital Tehran on Aug. 7, 2018. (AFP photo)

TEHRAN, Aug. 22 (Xinhua) -- Iran's Supreme Leader Ayatollah Ali Khamenei on Wednesday urged Muslims to unite against the U.S. "divisive" policies.

The call came as millions of Iranians are celebrating Eid al-Adha, or the Islamic "Festival of Sacrifice," across the country.

Meanwhile, Iranian President Hassan Rouhani expressed the hope that Muslims will overcome hostilities and extremism in his congratulations to leaders of Islamic countries on the advent of Eid al-Adha.

Iranian First Vice President Eshaq Jahangiri also called for "solidarity and unity of the Muslim world in the fight against violence, extremism and disloyalty of hegemonic powers."

Eid al-Adha is one of the holiest Islamic festivals to commemorate the willingness of Prophet Ibrahim to follow Allah's command to sacrifice his son.

Muslims around the world gather in the mosques, listen to the sermons and perform prayers during the five-day festival.