The British Museum is one of the most popular tourist attractions in the United Kingdom.
Greeks say the British Museum is unsafe after a series of thefts and is “blatant opportunism”, the chair of its all-party group has said.
MP Tim Loughton said it was “incredibly rare” for items to go missing and the institution took it “seriously”.
Archaeologist Despoina Koutsoumba said the museum could no longer claim that Greek heritage was protected.
Greece has long campaigned for the return of the Parthenon sculptures, also known as the Elgin Marbles.
The institution said a staff member was fired after treasures were reported “missing, damaged or stolen.”
Legal action has been taken by the museum against the anonymous staff member.
The Metropolitan Police’s Economic Crime Command is investigating but no arrests have been made. The museum also launched an independent security review.
Objects such as gold, jewelry and semi-precious stones are among the missing, although the museum has not specified which ones in particular.
It is now estimated that more than 1,500 items have been stolen, damaged and destroyed, in a crisis that threatens the reputation of the institution.
According to the PA news agency, the missing items are believed to have been recovered over a “significant” period of time.
Mr Loughton, who chairs the British Museum’s all-party parliamentary group, told BBC Radio 4’s Today program that news of objects from the collection disappearing in London was “damaging”, as were claims that the museum was not safe.
“What is particularly damaging is the blatant opportunism of the Greeks and others who say: ‘Oh no, the British Museum is not safe,'” he said.
The Conservative MP, who has been in contact with the museum, said it had undertaken “an enormous amount of work to catalogue” the objects in its collection and had the most extensive online documentation in the world.
“People want to know the extent of the items that have gone missing, what investigations were carried out at the time the various reports came in and what is being done now, otherwise it gets out of hand,” he added.
His comments follow renewed calls from Greek authorities for the return of the Parthenon sculptures, among the most high-profile contested objects in the museum’s collection.
The Parthenon sculptures, originating from the Temple of Athena in Greece, were imported to Britain by Lord Elgin.
Greece has long claimed they were acquired illegally during a period of foreign occupation.
Ms Koutsoumba, director of the Association of Greek Archaeologists, told BBC Radio 4’s World Tonight program that it was “obvious” that the sculptures would be well protected in Greece, not in the museum.
“We are very concerned about the number of Greek objects (among) these stolen objects and we want to tell the British Museum that they can no longer say that Greek cultural heritage is better protected at the British Museum,” she said .
“They need to return the Parthenon Marbles because they are not safe in London.”
She added that the potential security issues revealed by the thefts were a “problem for every museum in the world.”
“All museums around the world need to learn about what happened at the British Museum so that if we have any problems in our safety protocols we can change them,” she said.
The BBC has also seen correspondence showing that an art dealer alerted the museum to the allegedly stolen items in 2021.
Ittai Gradel claimed in February 2021 to have seen objects belonging to the museum online, according to correspondence.
Deputy Director Jonathan Williams responded in July 2021 to Mr. Gradel, saying “there was no suggestion of wrongdoing.”
The museum’s independent review is being led by the museum’s former trustee, Sir Nigel Boardman, and Lucy D’Orsi, head of the British Transport Police.
