Saudi Arabia said the hajj will start on June 14 after astronomical observatories spotted the crescent moon Thursday evening, signalling the beginning of the month in which the annual pilgrimage falls.
The Supreme Court determined that Dhu al-Hijjah, the 12th and final month of the Islamic calendar, would begin on Friday, the official Saudi Press Agency (SPA) said.
The hajj is one of the five pillars of Islam and must be undertaken at least once by all Muslims with the means.
It involves a series of rituals completed over at least four days in Mecca and its surroundings in the west of Saudi Arabia.
The high point comes on the second day, when pilgrims gather for prayers on Mount Arafat, where the Prophet Mohammed delivered his final sermon.
That will occur on June 15 this year, and the Muslim holiday of Eid al-Adha will fall on June 16, SPA said.
Saudi Arabia is home to the holiest shrines in Islam at Mecca and Medina, and the Gulf kingdom makes billions of dollars each year from the hajj and from pilgrimages, known as umrah, undertaken at other times of the year.
The pilgrimages are also a source of prestige for the Saudi monarch whose official title includes "Custodian of the Two Holy Mosques" in Mecca and Medina.
Last year more than 1.8 million Muslims took part in the hajj, according to official figures.
At a press conference on Thursday, Tawfiq al-Rabiah, the Saudi hajj and umrah minister, said "approximately 1.2 million pilgrims from various countries of the world" had already arrived in Saudi Arabia for this year's hajj.
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