The British Museum is not legally allowed to break up its vast collection which includes the Parthenon Marbles, the UK government said on Monday after news of secret talks emerged.
Greece, meanwhile, quashed reports that a deal with Britain over the repatriation of the Parthenon Sculptures to Athens was imminent but said talks have been taking place.
Greece has repeatedly called for the permanent return from the British Museum of the 2,500-year-old sculptures, also known as the Elgin Marbles, which British diplomat Lord Elgin removed from the Parthenon temple in the early 19th century when he was ambassador to the Ottoman Empire.
Museum chairman George Osborne and Greece's Prime Minister Kyriakos Mitsotakis have been in talks for a year, Greek newspaper Ta Nea reported on Saturday.
The British Museum's trustees are free to talk to whom they want, UK Prime Minister Rishi Sunak's official spokesman said on Monday.
“We have no plans to change the law, which prevents removing objects from the museum's collections, the British Museum's collections, apart from under certain circumstances,” he said. “Our position on that hasn't changed.”
Under the 1963 British Museum Act, which updated previous legislation, the museum can only sell or give away items from its collection under limited conditions.
Mr Sunak's spokesman refused to say whether the museum may be able to seek a special licence from the government to break up the collection.
The British Museum says its entire collection stretches to more than eight million objects, and only about 80,000 of them are on public display at any one time.
They include many items now considered by other countries as loot taken by builders of the British Empire, and the government has long been wary of setting a precedent with the marbles.
The British Museum has ruled out returning the marbles, which include about half of the 160-metre frieze that adorned the Parthenon, insisting that they were legally acquired.
The museum said in a statement on Monday it would not dismantle its collection “as it tells a unique story of our common humanity”.
However, it said it wanted to forge a new “Parthenon Partnership” with Greece.
“We are seeking new positive, long-term partnerships with countries and communities around the world, and that of course includes Greece,” it said.
Elgin sold the marbles to the government, which in 1817 passed them on to the British Museum. Greece maintains they were stolen and has long campaigned for their return.
Trustees can break up parts of the collection if “the object is unfit to be retained in the collections of the museum and can be disposed of without detriment to the interests of students”.