Greek Prime Minister Kyriakos Mitsotakis met UK leader Boris Johnson in London on Tuesday and told him the Elgin Marbles should be returned to Athens.
But Mr Johnson insisted that they would remain in the UK.
“I raised the issue ... today and I very much intend to continue working hard until the Parthenon sculptures have been returned permanently to the Acropolis museum,” Mr Mitsotakis said at an event at the Science Museum.
It is an emotional bone of contention for Greece, and one that often spills into the political arena.
At the start of the 19th century, Britain’s ambassador to the Ottoman Empire, Lord Elgin, removed the ancient sculptures from the Parthenon temple on the Acropolis hill and shipped them to England by sea.
For 200 years, prominent Greeks and national leaders have demanded them back. Mr Johnson’s spokesman has said it is a matter for the British Museum, where the artefacts are kept, and not for the UK government.
While Athens’ new Acropolis Museum, inaugurated in 2009, could house the treasures, the British Museum has been reluctant to support their return because it would mean the end of a major London tourist attraction.
“They’re here because they were stolen,” Mr Mitsotakis said in an ITV interview on Tuesday before the meeting with Mr Johnson.
“I don’t like to talk about the return of marbles, I like to talk about the reunification of the marbles.”
The Greek premier says the general argument for keeping the marbles at the British Museum is outdated.
“We want the sculptures back for good, so we won’t settle for a loan,” Mr Mitsotakis said.
But he has indicated some flexibility, suggesting that Athens could lend the British Museum some artefacts that have never left Greece as part of rotating collections.
“If there is a will I’m sure we can find a solution,” Mr Mitsotakis said.
