Greek Prime Minister Kyriakos Mitsotakis is expected to raise the contentious issue of the Parthenon Marbles during his visit to the UK early next week, in an attempt to resolve a centuries-long feud over the historical artifacts.

Mitsotakis is due to discuss the contested sculptures during meetings taking place early next week with British Prime Minister Rishi Sunak and opposition Labour Party leader Keir Starmer, people familiar with the matter said, as sticking points remain in the negotiations over returning them to Athens.

The Greek premier’s trip will be mainly focused on promoting the national economy, which recently regained the investment-grade status that it lost 13 years ago and is growing faster than most of its European peers. He will also speak to investors on Monday at a conference organized by Morgan Stanley and the Athens Stock Exchange.

London’s British Museum and Greece’s Acropolis Museum have been trying to broker an agreement that would see the artifacts — known to many in the UK as the Elgin Marbles — sent to Athens, from where they were removed in the early 19th century. Proposals mooted so far have included a long-term exchange that would send some of the marbles to Greece on rotation in exchange for other historical objects that would be loaned to the UK in return, or a multi-year “partnership” that could be easily renewed.

The British Museum hopes to find an arrangement that could get around a UK law prohibiting museums from “disposing” of objects abroad, at the same time as satisfying Greek demands to reunify the artifacts with those on display in Athens. One person involved in the discussions on the UK side said there had been some recent progress since they stalled at the beginning of the year, though noted that differences remained.

A spokesperson for the British Museum said in an emailed statement: “Discussions with Greece about a Parthenon Partnership are ongoing and constructive. We believe that this kind of long-term partnership would strike the right balance between sharing our greatest objects with audiences around the world, and maintaining the integrity of the incredible collection we hold at the museum.”

Greece won’t accept any deal that implies continued British ownership of the marbles, and does not expect an immediate breakthrough, a Greek government official said, playing down suggestions that a solution is imminent and asking, like UK officials, not to be named when discussing sensitive negotiations.

The UK foreign office and the Greek government did not immediately respond to requests for comment.

Any agreement would settle a dispute that’s plagued Anglo-Greek relations since the founding of modern Greece in 1832. The sculptures were taken from the Acropolis in Athens in the early 19th century by Lord Elgin, who was Britain’s ambassador to the Ottoman Empire at the turn of the century.

The British Museum argues the marbles were removed with approval of the legal authorities of the day in Athens, then under Ottoman rule, and that they were saved from loss and damage, which had befallen more than half of the Parthenon’s sculptures before 1800.

Along with Mitsotakis’s reelection this summer, the appointment of former UK premier David Cameron last week as Sunak’s new foreign secretary inserted a fresh dynamic into the talks. Cameron is a close friend of British Museum chair George Osborne, who served as his chancellor of the exchequer between 2010 and 2016, leading to optimism among some working on the deal. However, as prime minister, Cameron himself declined to negotiate on the matter, telling the House of Commons in 2011 that he did not want Britain to “lose its marbles.”

Osborne said in a speech earlier this month that he hoped he could “reach an agreement with Greece” that was “practical, pragmatic and rational,” again sparking speculation that a deal could be possible.

The fact that Mitsotakis intends to raise the marbles with Starmer as well as Sunak may yet suggest that he thinks talks will need to continue through the next UK election, which must be held by the end of January 2025. Starmer is on course to succeed Sunak as prime minister with his Labour Party leading the governing Conservatives by around 20 points in opinion polls.

“There is a growing consensus across the political parties that a ‘win win’ arrangement can be reached on the Parthenon Sculptures,” said Josh Lambkin, a spokesperson for the Parthenon Project, which is seeking a deal on the sculptures.

(Updates with British Museum’s position in 10th paragraph.)