Mosaics in Istanbul's ancient Hagia Sophia will be covered by curtains or lasers during times of Muslim prayer, the spokesman for Turkey's ruling AK Party said on Monday, after President Recep Tayyip Erdogan declared the museum would again be a mosque. The Christian icons would be uncovered and be open to all visitors at other times, and admission would be free of charge, the AKP's Omer Celik said. It was not immediately clear how the lasers would work. On Friday, a Turkish court ruled that the building's conversion to a museum in 1934 was unlawful and Mr Erdogan, declaring it a mosque, said the first prayers would be held there within two weeks. The move drew international criticism and concern, including from Greece, the United States and Russia, as well as Unesco and Pope Francis, who said he was hurt by the decision. Mr Celik told a news conference in Ankara that the biggest disrespect to Hagia Sophia in history was done by the papacy. He said Orthodox Christians and Hagia Sophia had suffered for years during a "Latin invasion" led by the papacy in the 13th Century when Crusaders pillaged the cathedral. Greece said the decision would have repercussions on relations between the two countries and on Turkey's ties with the European Union. The US State Department said it was "disappointed" by the move. The leader of Italy's far-right Lega Nord, Matteo Salvini, led a demonstration outside the Turkish consulate in Milan to protest against the decision. "I would stop every kind of financial aid to the Turkish regime and I would terminate once and for all any hypothesis of Turkey entering the European Union because we have given more than 10 billion euros (Dh 41 billion) to a regime that transforms churches into mosques and I think they have gone over the limit," he said. Unesco said on Friday that it would review the status of the monument as a World Heritage Site following Mr Erdogan's announcement. Foreign Minister Mevlut Cavusoglu said Ankara was surprised by Unesco's reaction and would let it know of further steps that will be taken regarding Hagia Sophia, which was a Byzantine church for nine centuries before the Ottomans converted it to a mosque. Turkey is sensitive about protecting its historical character, he said. "We have to protect our ancestors' heritage. The function can be this way or that way – it does not matter," Mr Cavusoglu told state broadcaster TRT Haber.