The Elgin Marbles, taken from the Parthenon, are at the center of this political rift

MARY LOUISE KELLY, HOST:

Greece's prime minister cut short a visit to London today after an apparent snub by his British counterpart over the Elgin Marbles. These are marble sculptures that were removed from the Acropolis in Athens in the early 19th century and are now housed at the British Museum in London. Greece wants them back, as NPR's Lauren Frayer reports.

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UNIDENTIFIED PERSON: Once upon a time, the Parthenon looked like this.

LAUREN FRAYER, BYLINE: The Parthenon was built in Athens in the fifth century BCE, and nobody living today has ever seen the friezes that covered its facade on display all together. In the early 19th century, Britain's ambassador to the Ottoman Empire, which Greece had been part of, got a permit to remove about half of those ornate marble sculptures. That ambassador's name was Lord Elgin, and those sculptures, which ended up in the British Museum, are better known as the Elgin Marbles. As former empires like Britain come to terms with their at times shameful past, calls are growing for the Elgin Marbles, just like Africa's Benin Bronzes or, some hope, South Asia's Koh-i-Noor diamond to be returned.

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PRIME MINISTER KYRIAKOS MITSOTAKIS: We feel that these sculptures belong to Greece and that they were essentially stolen.

FRAYER: That's Greece's Prime Minister, Kyriakos Mitsotakis, on the BBC this past weekend, speaking about how some of the Elgin Marbles remain in Athens while some are in London.

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MITSOTAKIS: If I told you that you would cut the "Mona Lisa" in half and you would have half of it at the Louvre and half of it at the British Museum, do you think your viewers would appreciate the beauty of the painting?

FRAYER: Britain's government disagrees, though. Education Secretary Gillian Keegan told local TV the Elgin Marbles are...

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GILLIAN KEEGAN: Actually protected under law, and under that law, they have to stay in the British Museum.

FRAYER: Apparently because of that legal permission Lord Elgin got from the Ottomans more than 200 years ago. This is a long-running debate, but it turned into a diplomatic spat today. U.K. media say Prime Minister Rishi Sunak had sought assurances that Mitsotakis would not raise the issue of the marbles on this London visit. And after he did, in that BBC interview, Sunak cancelled their planned meeting.

SARAH BAXTER: I think he wanted to sort of stoke some culture wars here.

FRAYER: Sarah Baxter is on the advisory board of the Parthenon Project, a group trying to find a compromise here. She says Sunak may be out of step with voters. Polls show a majority of Britons support the return of the Elgin Marbles to Greece, especially if that means more Greek antiquities could come here on loan.

BAXTER: The idea being that you don't just sort of leave the British Museum without these wonderful sculptures but that you can bring marvels over to the British Museum. The public, you know, would be queuing around the block to see things like the Mask of Agamemnon, for example.

FRAYER: Treasures that, unlike the Elgin Marbles, have remained in Greece. Lauren Frayer, NPR News, London. Transcript provided by NPR, Copyright NPR.