Palestinian Authority leader Mahmoud Abbas phoned Turkish President Recep Tayyip Erdoğan on Sunday to congratulate him for turning Istanbul’s iconic cathedral Hagia Sophia into a mosque,

According to the Turkish press, the phone call was reported by Turkey’s Communications Directorate, which released a statement claiming that during the conversation, Erdoğan reiterated Turkey’s determination to continue to support the Palestinian cause.

On July 10, Erdoğan declared that the “resurrection” of the ancient Hagia Sophia church as a mosque bodes well for the “liberation” of the Al-Aqsa Mosque in Jerusalem.

Built in the sixth century C.E. by the Byzantine Emperor Justinian, the Hagia Sophia served as the world’s largest Christian church for nearly 1,000 years until Constantinople (now Istanbul) fell to the conquering Ottoman Turks in 1453. They converted the church into a mosque until 1935, when Turkey’s secular president, Mustafa Kemal Atatürk, converted it into a museum open to all.