PUBLIC support can help save valuable works of art for the nation, staff at the Ashmolean Museum said yesterday.

Almost £300m of Britain’s most cherished artworks have permanently left the country since 2011.

Stephen Deuchar, director of the Art Fund, said the export system was abused by wealthy buyers using ‘exploitable loopholes’ and ‘gentlemen’s agreements’ to keep masterpieces out of public reach.

In 2012, the Ashmolean raised £7.8m needed to save for the nation, Manet’s portrait of Fanny Claus.

The appeal was backed by the public and prevented the painting from being sold abroad for £28m.

Ashmolean Museum spokeswoman Claire Parris said: “The Manet was a perfect example of how artworks can be saved from leaving the country and we got a lot of support from the public, who were keen that the painting should stay at the Ashmolean.”

Two years ago, The Adoration of the Magi, a marble carving at the museum by John Flaxman worth £800,000, was sold abroad after it had been on display.

Among the exodus of treasures nationwide was a £50m Picasso – Child With A Dove – which is now thought to be in Qatar.

Important cultural objects bought by overseas collectors are typically issued with a temporary export ban, giving British dealers or museums a chance to match the price.

About 32 national treasures, which are worth a total of about £70m, have stayed in the UK this way since 2011-2012, Arts Council figures showed.