The Islamic holy-month of Ramadan is set to start on Thursday 17 May in Egypt, the country's National Astronomy and Geophysics Institute announced on Sunday.
Ramadan takes place during the ninth month of the Islamic calendar, the month in which the Quran was revealed to the Prophet Muhammad. More than a billion Muslims around the world abstain from eating and drinking from dawn to dusk during Ramadan.
The head of the Egyptian institute, Hatem Aouda, said on Sunday that the crescent moon by which the start of Ramadan is measured will be seen on 15 May. This will mark the end of the eighth month of the Islamic calendar on May 16, the state-owned MENA news agency reported.
During the holy month, Muslims fast for a full lunar month. The fasting begins at the fajr call to prayer, just before sunrise, and is broken at sundown.
As the times for sunrise and sunset change each day, fasting hours in Ramadan also change by a few minutes throughout the month.
This year, there are expected to be an average of 15 fasting hours each day in Egypt. The length of fasting hours differs from one country to another.
In recent years, Ramadan has moved into the summer months, bringing longer days and sweltering heat for many countries, especially in the Middle East.
Eid Al-Fitr, or "the feast of breaking the fast", is a three-day religious holiday marking the end of the fasting month of Ramadan and celebrated by Muslims worldwide.