London, October 20 An Italian art expert is looking to put an end to decades of speculation regarding a long-lost Leonardo da Vinci masterpiece, claiming it maybe hidden in a secret cavity behind a palace wall.

University professor Maurizio Seracini alleges a clue in a huge artwork in Florence's historic Palazzo Vecchio appeared to suggest that The Battle of Anghiari, painted by Leonardo in 1503, his largest ever work, lied beneath.

"I have been searching the documents for many, many years and I have not come across anything which suggests that the painting was destroyed, damaged or removed. There is no evidence to hint that it is not there any more," the Telegraph quoted Prof Seracini as saying.

"It was considered by Leonardo's contemporaries to be his foremost masterpiece. It represented the highest achievements in art reached at the time, during the early Renaissance," he added.

The expert has finally been given the permission to use state-of-the-art equipment to determine if the artwork, believed to be three times the size of Leonardo's Last Supper, was painted over with the fresco.

Marco Agnoletti, a spokesman for Florence's mayor Matteo Renzi, said: "For now, we just want to find out whether the Leonardo painting is there or not. We may find nothing. But if there really is a work by Leonardo, it would be of huge importance to the whole world." (ANI)