Russian Orthodox Church criticises Turkey's Hagia Sofia mosque conversion plans
"Any attempts to change the museum status of Hagia Sophia Cathedral will lead to changing and violating fragile inter-confessional balances," the church's head of External Church Relations, Metropolitan Hilarion, was quoted as saying by the Orthodox Times.
Right-wing Turks have long discussed converting the museum - originally built as a church by the Byzantines - into a mosque.
The heated debate around returning Istanbul's Hagia Sophia to its Ottoman status as a Muslim place of worship highlights the sharp divide between conservative and secular Turks, but also threatens to increased tensions with neighbouring Greece.
In 1934, it was converted to a museum as part of efforts by the new Turkish Republic to secularise and move away from the country's Ottoman heritage.
Last month, Turkey held Muslim prayers in the Hagia Sophia to commemorate the anniversary of the Ottoman conquest of Istanbul, previously known as Constantinople.
The act elicited outrage from Greece, further compounded by Turkey's President Recep Tayyip Erdogan ordering a study earlier this month into the museum's conversion into a mosque.
"Greece is not the one administrating this land, so it should avoid making such remarks," Erdogan said on Monday.
"They're saying, 'Don't turn Hagia Sophia into a mosque'. Do you rule Turkey, or do we rule Turkey?"
Hilarion, the Russian Orthodox Church official, also voiced concerns that the Hagia Sophia's transformation into a mosque would mean access would be restricted to visitors of other faiths. It should remain a museum, Hilarion said.
"This church is a symbol of Byzantium and a symbol of Orthodoxy for millions of Christians all around the world, especially for Orthodox believers," the Metropolitan stated.
The Turkish president has previously stated that, if converted into a mosque, the Hagia Sophia would remain open for visitors, comparing it to Istanbul's famous Blue Mosque.
A Turkish court is expected to rule on the matter in early July.
Rather than reflecting any real intention to convert the Hagia Sophia into a mosque, recent comments by Erdogan and other Turkish officials may signal upcoming snap elections, analysts say.
Critics accuse the ruling party of using the religious debate as a means to bolster support amid an economic crisis.
The debate also comes amid rising tensions with Greece. Over the past few months, the neighbouring countries have locked horns over territorial issues, including over gas drilling in the Mediterranean and over Cyprus.
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