The British government also said it had no plans to change laws which prevent the removal of such items from the Britsh Museum's collection. The museum, custodian of the sculptures known in Britain as the Elgin Marbles, also reiterated it would not dismantle its collection.

Greece has repeatedly called for the permanent return from the British Museum of the 2,500-year-old sculptures, which British diplomat Lord Elgin removed from the Parthenon temple in the early 19th century when he was ambassador to the Ottoman Empire, Greece's then-ruler.

Greece's Ta Nea newspaper on Saturday reported that negotiations were at an advanced stage and cited a Greek source as saying that an agreement was 90% complete but that "a critical 10% remains unresolved".

"Since the beginning of its term the government has been and is in talks with the British side," government spokesman Giannis Oikonomou said on Monday when asked about the media reports.

"These discussions are at a preliminary stage. We are far from announcements or a final deal," he said.

Last week, Greek Prime Minister Kyriakos Mitsotakis, who faces elections in 2023, said that there was "progress" and a sense of "momentum" in talks with Britain to reunite the sculptures in Greece.

The British Museum has always ruled out returning the marbles, which include about half of the 160-metre (525-ft) frieze that adorned the Parthenon, and insists 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.

Asked about British Prime Minister Rishi Sunak's position on their return, a spokesman said Britain had no plans to change laws which prevent removing objects from the collection apart from in certain circumstances.

"Our position on this hasn't changed. Decisions relating to the care and management of the collections are a matter for the museum and its trustees," the spokesman said.

Citing a British official, Greece's ANT1 TV said on Sunday that the only way to return the sculptures to Greece without violating British law was "if the British Museum opened a kind of annex in Greece".

In March, the United Nations' cultural agency UNESCO urged Greece and Britain to reach a settlement on the issue.

Greece stepped up its campaign for the return of the marbles after opening a new museum in 2009 at the foot of the Acropolis hill that it hopes will one day house them.

In 2019, Greece said it could loan treasures to the British Museum in return for being able to temporarily exhibit the Parthenon marbles and that such a proposal was not altering its long-standing demand for their permanent return.

This year, the so-called "Fagan fragment", a 35-by-31-cm (12-by-14-inch) piece showing the foot of the seated ancient Greek goddess Artemis, which was part of the 5th century BC temple's eastern frieze, was permanently returned to Athens from a museum in Italy.