The Saudi monarch "sent a written letter to President Mahmoud Ahmadinejad inviting him to attend the extraordinary Islamic solidarity meeting which will be held in Mecca" in mid-August, SPA reported.

Tensions have been running high between the Sunni-dominated kingdom and Shiite Iran as both regional powers had taken opposite stances on the uprisings in Bahrain and Syria.

Iran had voiced support to a Shiite-led uprising in Bahrain which Saudi Arabia had sent troops to crush last year.

accused of sending military aid to the Syrian government. Tehran has denied the claims.

Saudi Arabia last month called for the summit in a bid at "unifying the ranks" of Muslims.

Saudi Arabia hosts the headquarters of the 57-member pan-Muslim body -- the Organisation of Islamic Cooperation which is based in the Red Sea city of Jeddah.