London ? Several of the world’s leading museums defended the British Museum’s right to keep ancient statues taken from the Parthenon 200 years ago, despite Greek demands for their return.

A letter signed by the directors of 18 museums, including the Louvre and the Metropolitan Museum of Art, said works acquired decades ago had become essential to the museums that house them.

“Objects acquired in earlier times must be viewed in the light of different sensitivities and values, reflective of that earlier era,” the statement said.

The museum directors’ statement was presented to the British Museum, which released it to The Sunday Times newspaper, Jonathan Williams, assistant to the museum’s director, said Wednesday.

Though the statement did not mention the so-called Elgin Marbles, it was clearly a response to a dispute between the British Museum and Greece over the 17 figures and part of a frieze that decorated the Parthenon atop the Acropolis.

They were removed by Lord Elgin, Britain’s ambassador to the Ottoman Empire, and have been housed in the British Museum in London since the early 19th century. The pieces date from the 5th century B.C.

Athens is pressing for their return by 2004, when the city be host to the Olympic Games.

The British Museum says the marbles were acquired legally from the Ottoman government that controlled Greece at the time.

Other signatories of the statement included the Hermitage in St. Petersburg, Russia, the Opificio delle Pietre Dure in Florence, Italy, and the Prado in Madrid, Spain.