The Muslim festival of Eid al-Fitr that marks the end of the holy fasting month of Ramadan will begin on Monday in Saudi Arabia and neighbouring states.
The religious authorities in the desert kingdom announced on Sunday they had received reports of sightings of the new moon, marking the end of Ramadan.
"Eid al-Fitr will therefore be celebrated from Monday," an official statement said.
Kuwait, Lebanon, Qatar, Syria, the United Arab Emirates and Yemen have all also said the festival will begin in their countries on Monday.
During Ramadan, observant Muslims do not drink, eat or have sexual relations between dawn and nightfall.