ACADEMICS in Germany have questioned whether Michelangelo sketches kept at the Ashmolean Museum, Oxford, are genuine.

Three academics have written a five-volume study which casts doubt on the origins of the work.

They are among 40 per cent of surviving sketches by the Italian Renaissance master they believe should be dismissed as copies. The other alleged copies are in the Royal Collection and the British Museum.

Two sketches for the work entitled The Brazen Serpent are at the Ashmolean.

Timothy Wilson, Keeper of Western Art at the museum in Beaumont Street, said: "The Ashmolean welcomes intelligent and informed debate about all aspects of works of art in its care.

"There are very detailed and authoritative catalogue entries for all the drawings attributed to Michelangelo in the Ashmolean.

"We look forward to seeing the new studies by the German scholars published in detail and forming an assessment of them."

The three academics argue that hundreds of drawings by Michelangelo cannot be circulating worldwide when contemporary accounts refer to the artist burning most of them.

Michelangelo, who died in 1564, created two of the most influential works in fresco in the history of Western art - the scenes from Genesis on the ceiling, and The Last Judgement on the altar wall, of the Sistine Chapel at The Vatican in Rome.