An extraordinarily rare painting worth more than $60 million was recently discovered in Queen Elizabeth's storeroom.

The work of art had been dismissed as just a copy of "The Calling of Saints Peter and Andrew" by renowned 17th century artist Michelangelo Merisi da Caravaggio for decades. However, Italian scholar Maurizio Marini recognized the painting as an original and, after a complete clean, a selection of the world's most distinguished art experts confirmed its authenticity.

Connoisseur Sir Dennis Mahon told Britain's The Times newspaper, "It's been stripped down and cleaned. It's pretty clear it's original."

The painting - which was bought by King Charles I nearly 400 years ago - is one of only 50 surviving Caravaggio canvases.

Desmond Shawe-Taylor, surveyor for the queen's pictures, said, "We are extremely excited, it's the most important discovery in the collection in the last decade."

The picture will be displayed in "The Art of Italy" exhibition at Buckingham Palace next year.

Caravaggio, once Rome's most celebrated painter, is revered for his amazing use of light and strong narrative.