Palestinian President Mahmoud Abbas, Turkish President Tayyip Erdogan, Russian President Vladimir Putin and Chairman of the Council of Muftis of Russia Ravil Gainutdin attend a ceremony to open the Moscow Grand Mosque in Moscow, Russia, September 23, 2015. The new mosque, which was erected on the site of the city's original mosque built in 1904 and which has been under reconstruction since 2005, will be able to accommodate up to 10,000 people simultaneously, according to local media. Photo by Thaer Ganaim