An ancient church in Turkey could be turned into a mosque, despite the pleas of local Syriac Christians who want to restore it to its former glory.

The Mor Yuhanna church in Mardin, south-eastern Turkey, is believed to have been built in the fourth century. It is currently being used as a warehouse and carpentry, but its current owner,  Ibrahim Aycun, has put it on the market for US $4.5 million dollars – far more than the local Christian community can pay. The Daily Sabah website reports that neighbours claim Aycun wants the building converted into a mosque, though he has refused to comment.

Turkey has a strong Christian heritage – the apostle Paul and Timothy were both born there, and the city of Antioch, now Antakya, was known as "the cradle of Christianity" – but a series of genocides in the early 20th century killed much of the Christian population. The collapse of the Ottoman Empire in 1923 also forced many Armenians, Assyrians, Greeks and Georgians to leave the country, and the population of Turkey is now more than 97 per cent Muslim.

According to the Daily Sabah, many churches in Turkey seized by the State decades ago were given to private owners, making it difficult to return them to the faith community.

Rev Gabriel Akyüz from Mardin Kırklar Church confirmed that attempts to purchase the Mor Yuhanna church back have been made, but have so far failed. "We have a long-standing friendship with him [Aycun] and repeatedly asked him to hand over the church to the community because we did not want him to use this place as a warehouse," he explained.

"We would have the church restored and it would boost Mardin's tourism revenues. But he always asked for a high price.

"We cannot afford to pay the 12 million Turkish lira he asked for. We told him that we would erect a statue of him in the courtyard if he hands it to us but our efforts were fruitless."

One of the most widely contested religious buildings in Turkey is Hagia Sophia in Istanbul. Originally a church for 600 years, it was turned into a mosque in the 1400s and later closed in 1931.

The secular Turkish government turned it into a museum in 1935, but there have been calls for it to be re-opened as a mosque by the increasingly Islamist government of Recep Tayyip Erdogan.