PARIS, July 10. /TASS/. The United Nations Educational, Scientific and Cultural Organisation (UNESCO) expressed its regrets over the Turkish government’s decision to change the status of Hagia Sophia without prior discussions.

"The Director-General of UNESCO deeply regrets the decision of the Turkish authorities, made without prior discussion, to change the status of Hagia Sophia," the organization said. "This evening, she shared her serious concerns with the Ambassador of Turkey to UNESCO."

According to UNESCO chief Audrey Azoulay, "Hagia Sophia is an architectural masterpiece and a unique testimony to interactions between Europe and Asia over the centuries."

"Its status as a museum reflects the universal nature of its heritage, and makes it a powerful symbol for dialogue," Azoulay said.

UNESCO called upon the Turkish authorities "to initiate dialogue without delay, in order to prevent any detrimental effect on the universal value of this exceptional heritage." The building's state of conservation will be examined by the World Heritage Committee at its next session.

According to the international organization, the Turkish government’s decision raises the issue of how the change of status will affect the property’s universal value. In this regard, UNESCO reminded Turkey of its obligation "to ensure that modifications do not affect the Outstanding Universal Value of inscribed sites on their territories."

"UNESCO must be given prior notice of any such modifications, which, if necessary, are then examined by the World Heritage Committee," the organization said.

Meanwhile, UNESCO’s Assistant Director-General for Culture Ernesto Ottone urged "to avoid any implementing measure, without prior discussion with UNESCO, that would affect physical access to the site, the structure of the buildings, the site’s moveable property, or the site’s management."

In his words, such measures could constitute breaches of the rules derived from the 1972 World Heritage Convention.

Earlier on Friday, the Turkish Council of State has cancelled the Turkish government’s decree on assigning the museum status to Hagia Sophia.

The Hagia Sophia cathedral in Istanbul is an example of Byzantine architecture built in 532-537 on the orders of the emperor Justinian. After the fall of the Byzantine Empire the cathedral was converted into a mosque in 1453.

In 1935, according to a decree signed by the founder of the modern Turkish state Mustafa Kemal Ataturk, the cathedral became a museum and the plaster was cleared off the frescoes and the mosaics. In 1985, the building was included on the UNESCO World Heritage list.