The letters indicate that "There was no legality whatsoever in Elgin's acquisition of the Marbles and he knew it well, " she said.

BBC: To sue or not to sue? Parthenon Marbles activists debate

Perhaps if the British Museum were to acknowledge Greece's rightful ownership of the marbles then the time may come when Athens could lend the sculptures to other museums including the British Museum.

ECONOMIST: Rocks of ages

Former MP Andrew Dismore said a challenge now to the British Museum's right to have acquired the marbles in 1816 faced insurmountable obstacles.

BBC: To sue or not to sue? Parthenon Marbles activists debate