UNESCO said on Friday its World Heritage Committee would review Hagia Sophia’s status after Turkish President Tayyip Erdogan declared the Istanbul monument a mosque. “It is regrettable that the Turkish decision was not the subject of dialog nor notification beforehand,” the United Nation’s cultural body said in a statement. “UNESCO calls on the Turkish authorities to open a dialog without delay in order to avoid a step back from the universal value of this exceptional heritage whose preservation will be reviewed by the World Heritage Committee in its next session,” it said.