This year, Muslims around the world will celebrate Eid al-Adha (the Feast of Sacrifice), which marks the culmination of the annual Hajj pilgrimage, on Thursday, September 24.
They traditionally celebrate the occasion with the sacrifice of animals like sheep, rams, goats and cattle.
Larijani in his message described Hajj as a unique religious obligation whose lesson for humanity is enhancing the spirit of fraternity and unity under the banner of Tawhid (monotheism), ISNA reported.
He added that unity is the urgent need of the Muslim Ummah today, especially against the Takfiri extremist groups.
Elsewhere in his message, Larijani said Iran’s parliament support every measure aimed at boosting all-out cooperation among Muslim countries.