Hundreds, mostly Orthodox Christians, protested against the reconversion of Istanbul's Hagia Sophia into a mosque, Athens, Friday.
Believers were seen gathering in Kolokotroni square, with banners decrying the decision. People later held prayers at the Metropolitan Cathedral of the Annunciation.
Earlier the same day in Istanbul, Turkish President Recep Tayyip Erdogan participated in the first prayer at the Hagia Sophia, reading from the Quran at one point.
On July 10, Turkey's Council of State ruled that the museum had to be turned back into a place of worship, overturning a 1934 decree. UNESCO expressed concerns about the impact it may have on the universal value of the site, while the EU has called on Erdogan to reverse the decision.