The Iranian capital Tehran is set to hold the 31st the International Islamic Unity summit on December 5 to 7.
The theme of this year’s summit is "Unity and Requirements of New Islamic Civilization”.
The annual event, organized by the World Forum for Proximity of Islamic Schools of Thought (WFPIST), marks the Islamic unity week.
The 17th day of the month of Rabi al-Awwal in the lunar Hijri calendar, which falls on December 6 this year, is believed by Shia Muslims to mark the birth anniversary of Prophet Mohammad (PBUH), while Sunni Muslims regard the 12th day of the month as the birthday of the last prophet.
The interval between the two dates is celebrated every year as the Islamic Unity Week.
Late founder of the Islamic Revolution Imam Khomeini declared the occasion as the Islamic Unity Week back in the 1980s.