The court ruled on Friday that the 1934 decree converting the ancient Byzantine cathedral into a museum was not lawful. President Tayyip Erdogan has proposed re-purposing the building as a mosque.
Dating back to the 6th century, the Hagia Sophia is one of the most visited cultural sites in Turkey, as well as a UNESCO World Heritage Site.
UNESCO has expressed concern over Erdogan’s vision for the historic structure, noting in a statement on Friday that the building has a “strong symbolic and universal value.” It called on Turkey to "engage in dialogue" before taking any steps that might impact its universal value.
Erdogan is expected to deliver an address about the court ruling later on Friday.
The Turkish president’s intentions to turn the structure into a mosque have been condemned by leaders of the Russian and Greek Orthodox churches, who have warned that it would be seen as an affront to Christians and create a fracture between East and West. Washington has also urged Turkey to maintain the Hagia Sophia as a museum.
