The crescent moon was sighted on Sunday evening in Sudair and Al-Hariq, Arab media reported.
However, Oman has declared Tuesday as the first day of the holy month of Ramadan.
Ramadan is the ninth month of the Islamic calendar during which Muslims fast from dawn to sunset, abstaining from food and drink.
The holy month is a period of introspection and community, when Muslims read the Qur’an more than usual, perform taraweeh prayers, and increase their good deeds including charitable giving.
MNA