United: Allan, Shaw, Redgrave and Suzman
The Parthenon 2004 campaign pledged to make the British government and museum curators send back the ancient sculptures in time for the Olympics in Athens in 2004.
Prime Minister Tony Blair and curators at the British Museum are adamant the historic sculptures will not be returned to Greece, even on loan.
The marble friezes were removed from the Acropolis two centuries ago by the then British ambassador and are now housed in the British Museum in London.
In 2001, the Greek Culture Minister Evangelos Venizelos made a plea to the UK to allow the marbles to travel to Greece in time for the Olympics, 108 years after the first modern games were held there.
Despite a refusal Greece is building a new £29m Acropolis museum in which it hopes to house the sculptures.
"The Parthenon without the marbles is devalued and the
marbles are devalued by not being in their rightful
place," said Liberal Democrat MP Richard Allen, a
former archaeologist.
He added: "We want to draw a line under the debate over whether the marbles were legally obtained, and look forward to the question of where they can best be displayed in the future."
Others supporting Parthenon 2004 include former sports minister Tony Banks and former labour leader Michael Foot.
But the director of the British Museum, Robert Anderson, has turned down calls for them to be loaned out.
Mr Anderson told the BBC the marbles "belonged to the British Museum and the international public who come to the British Museum".
The 56 sculpted friezes were sent to the museum after their removal from Greece during Ottoman Turkish rule.
Known in Greece as the Parthenon sculptures, they date from between 447 and 432 BC and depict the most formal religious ceremonies of ancient Athens - the Panathenaea procession.
Defamed
In 1799 the British ambassador to the Ottoman Empire, Lord Elgin, removed the friezes and brought them to the UK.
Mr Anderson wrote in The Times that Elgin had been unjustly "defamed" by the campaign to restore the pieces to Greece.
He added that at Elgin's time the Parthenon was a ruin, having been damaged by an explosion at the end of the 17th Century.
"We are indebted to Elgin for having rescued the Parthenon sculptures and others from the Acropolis from the destruction they were suffering," he wrote.