Boris Johnson has come under fresh pressure over the future of the Elgin Marbles after the Greek Prime Minister urged him to ‘seize the moment’ and return the historic artefacts to Athens.

Kyriakos Mitsotakis, writing in today’s Mail on Sunday, says when he met Mr Johnson in Downing Street last week, the Prime Minister promised not to ‘stand in the way of Greece establishing a formal dialogue with the British Museum over the future of the marbles’.

Mr Mitsotakis has offered to lend some of his country’s treasures, such as the Artemision Bronze – an ancient Greek sculpture of Zeus or Poseidon – to the UK in exchange for the return of the 2,500-year-old sculptures, which were removed from the Parthenon by British envoy Lord Elgin between 1801 and 1812.

The UK’s long-standing position has been that the Elgin Marbles were acquired in accordance with the law, and any decision on their return has to be made by the British Museum, which operates independently of the Government and free from political interference.

The Greek PM has asked Boris to return the Elgin Marbles (pictured) to Athens

The Greek PM has asked Boris to return the Elgin Marbles (pictured) to Athens

The people who are against returning them say it will set a precedent that could trigger the trading of historic treasures across the globe.

Arguing that classics scholar Mr Johnson ‘understands the unique bond that ties modernity to ancient history’, Mr Mitsotakis says the Prime Minister has acknowledged the strength of feeling among the Greek people.

He writes: ‘This year marks the 200th anniversary of Greece’s war of independence against the Ottoman Empire, a war in which Britain stood with Greece in the fight for freedom.

‘What greater manifestation of the Prime Minister’s vision of a new, self-confident, open, and truly global Britain could there be, then, than for his government to take a bold step forward and, with the British Museum, repatriate the Parthenon Sculptures?’

He adds: ‘Reuniting the marbles would be made very much easier if the British Government cut the political restraints in the form of the British Museum Act of 1963 that tie the hands of the museum.

Mr Mitsotakis has offered to lend some of his country¿s treasures, such as the Artemision Bronze to the UK in exchange for the return of the artefacts

Mr Mitsotakis has offered to lend some of his country’s treasures, such as the Artemision Bronze to the UK in exchange for the return of the artefacts 

Greek PM Kyriakos Mitsotakis

Prime Minister Boris Johnson

Mr Mitsotakis said Mr Johnson has told him he ‘would not stand in the way of Greece establishing a formal dialogue with the British Museum over the future of the marbles’

‘Now, given that the Prime Minister has told me he would not stand in the way of Greece establishing a formal dialogue with the British Museum over the future of the marbles, I can only assume that … he will not obstruct any future agreement and that, instead, the Prime Minister would seek to amend the relevant legislation to allow the sculptures’ return.’

M. Mitsotakis claims that his call for them to be returned from the British Museum was bolstered because polls show that a greater number of Britons are in favor of repatriation.

According to the most recent poll, 62% of respondents support restoring artifacts back to their countries of origin. Only 15% are against.

The human rights lawyer Amal Clooney, the wife of Hollywood actor George Clooney – who has himself clashed with Mr Johnson over the fate of the Marbles – is advising the Greek culture ministry on its options.

It is argued that the main legal reason for keeping them by the United Kingdom was Lord Elgin’s permission to have them as a permit from the Ottomans. The Ottomans ruled Greece during this time.

Mr Mitsotakis says his demand for their return from the British Museum has been bolstered by the fact that polls point to a growing majority of Britons in favour of repatriation

M. Mitsotakis claims that his desire for them to be returned from the British Museum was bolstered because polls show that an increasing number of Britons are in favor of repatriation

Amal Clooney, the wife of Hollywood actor George Clooney ¿ who has himself clashed with Mr Johnson over the fate of the Marbles ¿ is advising the Greek culture ministry on its options

Amal Clooney, the wife of Hollywood actor George Clooney – who has himself clashed with Mr Johnson over the fate of the Marbles – is advising the Greek culture ministry on its options

The Greeks, however, claim that permit was faked and the Ottoman Empire wasn’t an occupying power that represented the will of the Greeks.

If the Athens government succeeds, they will reunite the treasures with Lord Elgin’s sculptures, which are now housed at a museum near the Parthenon.

Mr Mitsotakis writes: ‘Neither the frieze nor the Parthenon can be viewed as complete without the missing sculptures.’

There is a rising trend from France, Germany, and Belgium for the British Government to return colonial artifacts taken from countries occupied during their Colonial eras. 

Ex-Chancellor George Osborne is the chairman of its trustees. Yesterday’s comment request was not returned by the museum.