NEW DELHI (WION) — The court is set to rule on July 2 on a challenge to the current status that disputes the legality of the decision taken in 1934 to convert Hagia Sophia into a museum.

Groups have campaigned for years for Hagia Sophia’s conversion into a mosque and Erdogan, a pious Muslim, backed their call ahead of local elections last year.

Ecumenical Patriarch Bartholomew reacted by saying “The conversion of Hagia Sophia into a mosque will disappoint millions of Christians around the world.

Built as the great Cathedral of the Eastern Roman Empire, Hagia Sophia or Sancta Sophia (“Holly Wisdom”) was the seat of the ecumenical patriarch of Constantinople until the city fell to Ottoman conquest in 1453. It remained the largest cathedral in the world for almost a thousand years until the Seville Cathedral was completed in 1520. It was converted by the Ottomans into a mosque until 1931. It was then secularized by Attaturk and opened as a museum in 1935.