ATHENS, April 15 (Xinhua) -- Greece reiterated on Monday a long-standing call for the return of the Parthenon sculptures from the British museum to their homeland during an international conference hosted at the Acropolis museum in Athens.

"The struggle for the restoration of what is undoubtedly a most emblematic World Heritage Monument concerns not only Greece," Greek President Prokopis Pavlopoulos said opening the forum.

"It is universally acknowledged that these sculptures belong rightfully and culturally to the Parthenon," he said, according to Greek national news agency AMNA.

In the early 19th century, while Greece was still under Ottoman Empire rule, half of the sculptures of the Parthenon temple, which was constructed 2,500 years ago on the Acropolis hill, were removed by Lord Elgin, a UK diplomat at the time, and ended up at the British Museum in London.

Since the establishment of the Greek state a few years later, Greeks have repeatedly asked for the repatriation of the Parthenon sculptures.

The new Acropolis museum which was inaugurated in June 2009 was constructed to invalidate one of the arguments of those who claimed that Greece does not have a suitable place to host and protect the sculptures, Pavlopoulos said.

Addressing the conference, Professor Dimitrios Pandermalis, Director of the Acropolis museum, said that the results of recent scientific researches deprive the British side from another key argument in the case.

The British Museum has dismissed the requests for the sculptures' return for decades, arguing that Lord Elgin had permission of Ottoman authorities under a legal contract.

Recent findings by Turkish academics Professor Zeynep Aygen and historian Orhan Sakin who research the Ottoman Empire archives, as well as Greek experts' own research into archives of this period, cast doubt on such claims, Pandermalis said, according to AMNA.

There was no official license given to the British diplomat for the transfer of the sculptures, the Greek Professor argued on Monday.

The only person in the Empire with the authority to allow a monument to be moved was the Sultan himself, he explained.

The document that is preserved and presented as such a decree by the British side, is not actually an official order, but an administrative letter from a Governor of the Empire to the authorities of Athens, Pandermalis said.

"It is very clear that it is not a permit that allows the Parthenon to be stripped bare, but a permit for the excavation of volumes of earth around the Parthenon," he added.