British Prime Minister Rishi Sunak has reportedly cancelled a planned meeting on Tuesday with his Greek counterpart, Kyriakos Mitsotakis, during a visit to the UK amid a deepening row over the return of the 'Elgin Marbles'.

The ancient Greek sculptures from the Parthenon in Athens are among the controversial historic items which were brought to the UK by British diplomat Lord Elgin in the early 19th century – giving them their English name.

The Parthenon Sculptures now form part of the British Museum’s collection and have long been demanded by the Greeks to complete their series at the Acropolis Museum in Athens.

The latest standoff is reminiscent of India’s demands for the Koh-i-Noor diamond and other historic artefacts taken from India during colonial times. Most recently, the Maharashtra government signed a memorandum of understanding (MoU) with the Victoria and Albert Museum for a three-year loan of a set of 17th century ‘Tiger Claws’, or wagh nakh, believed to have belonged to Chhatrapati Shivaji Maharaj. It is destined for Mumbai’s Chhatrapati Shivaji Maharaj Vastu Sangrahalaya (CSMVS) as part of Maharashtra’s 350th anniversary celebrations of the coronation of Chhatrapati Shivaji.

The UK-Greece standoff seems to have erupted after Downing Street claimed that it had been agreed that the issue would not be raised during any bilateral between Sunak and Mitsotakis, a claim denied by the Greeks.

On Sunday, the Greek Prime Minister told the BBC that having some of the Parthenon treasures in London and others in Athens was like cutting the 'Mona Lisa' painting in half.

That seems to have triggered the row, as Mitsotakis then told reporters on Monday evening that he was “deeply disappointed by the abrupt cancellation” of his meeting with Sunak, which had been planned for Tuesday afternoon.

“Those who firmly believe in the correctness and justice of their positions are never hesitant to engage in constructive argumentation and debate,” said the Greek Prime Minister.

“Britain's attitude shows no respect for the Prime Minister and our country,” his government spokesperson later told SKAI TV.

He added that although cancelling a meeting was not “common,” the Greek government did not want “to escalate the issue with a country with which we have good relations.” The Greek leader was offered a meeting with UK Deputy Prime Minister Oliver Dowden, which his team declined and chose to head back instead. The row comes against the backdrop of the British Museum chair, former chancellor George Osborne, indicating recently that he was open to considering a loan of the sculptures to Greece.

Many within the governing Conservative Party are opposed to such an idea but the official government stance has been that it is a matter for the museum. Sunak, preparing for a general election next year, is seemingly positioning himself decisively on one side of that argument that is against any sort of return of the treasures.

The Opposition Labour Party has been stinging in its reaction, expressing shock at the government opening up a fight with a North Atlantic Treaty Organisation (NATO) ally.

“To pick a fight with a NATO ally for the sake of a headline shows just how weak Rishi Sunak is. He should have been talking about the economy, immigration, the Middle East, that's what the country would expect from a leader but Rishi Sunak is no leader,” a Labour spokesperson told the BBC.

The Opposition party, currently ahead in the opinion polls, says its position is that if the British Museum and the Greek government came to a loan agreement, a future Labour government would not stand in the way.

While the 1963 British Museum Act prevents the world-famous museum from giving away objects from its collection except, in very limited circumstances, a loan of its artefacts would not require a law change.

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