Organisers of a campaign to keep a Renaissance masterpiece on public view are convinced that they will succeed after receiving a £10 million donation for their fighting fund.

Nicholas Penny, the director of the National Gallery, said yesterday that he was “previously pretending to be optimistic but now I am genuinely optimistic” after the National Heritage Memorial Fund announced the donation.

The campaign now needs “much less than £30 million” to secure Titian’s Diana and Actaeon for future generations, he said.

The National Gallery and the National Galleries of Scotland are attempting to raise £100 million to buy the work and its companion piece, Diana and Callisto. The galleries have until the end of the year to prove that they can afford the first £50 million instalment, for Diana and Actaeon.

Times Archive, 1933: The Bridgewater Titians

'Actaeon' is the most complete and satisfying of the paintings, as it is the one that has suffered least by time

• The conservation of pictures

• Picture: The vapour chamber used by Mr Kennedy North for the conservation of Titian's painting, Diana and Actaeon

Related Links

• Why we must save Titian's masterpiece

• Galleries optimistic they can pull off a masterstroke and buy the Titian

• Save the Titians - change the system

The paintings are owned by the 7th Duke of Sutherland, who is threatening to sell them on the open market. They are the star attractions of the Bridgewater Collection, which has been on loan to the National Galleries of Scotland for 63 years.

In August The Art Newspaper valued the Titians at £300 million, which would make the Duke’s price of £50 million per painting a bargain. Some experts have questioned that figure, however, noting that the record for a Titian at auction is £7.48 million.

The galleries, which would share the paintings if successful, are looking to their respective governments for further contributions. “We have to have support from government in one form or another,” Mr Penny said.

Barbara Follett, the Culture Minister, said that keeping the Titians was a priority but gave warning that the financial crisis had made it “harder to make the case and, more importantly, much harder to find the money”.

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