Some of the National Gallery's most outstanding Renaissance paintings could become the subject of legal action to reclaim them after the gallery was accused of failing to honour the donor's last wishes.
The £500m collection of 43 masterpieces, including works by Raphael, Titian and Botticelli, were donated by Ludwig Mond, a German Jewish émigré, in the 1920s on the condition they remain "substantially united".
His family say the paintings have become scattered and the gallery may have forfeited its right to them by breaking the terms of the bequest, it was reported last night.
Richard Hornsby, Dr Mond's great-great-grandson, accused the museum of "theft by any other name".
"This is disgraceful treatment towards one of its greatest donors," he said, adding that he could no longer tolerate the gallery's refusal to observe conditions of the original will.
The family funded half the cost of the Mond Room to house the works of art, though it is now filled with Van Dycks.
Some of the paintings are now hanging in the Lower Galleries, currently open only on Wednesdays, while others have been put into storage. Two works are on loan to the British Museum.
"By stealth, Mond pictures have been placed according to curators' preferences in historical order and scattered throughout the gallery," said Mr Hornsby, 54, chief executive of the Sir Robert Mond Memorial Trust, a mental health charity.
"All that remains of the collection is a small plaque in the Mond Room saying that the room was built with a donation from the Mond family."
Leolin Price QC, who has been contacted by the family, added: "If there are terms of the bequest, the family may, when investigated, have a right to recover what has been given without accepting the terms."
Dr Mond, a pioneering industrialist and chemist who came to England in 1867 and laid the foundations of ICI, left the bequest to the National Gallery to reflect his gratitude to his adopted nation.
A gallery spokeswoman said: "The National Gallery is proud to house the paintings so generously bequeathed by Dr Ludwig Mond. They include some of the gallery's most outstanding Renaissance paintings, most famously Raphael's Crucified Christ, which has central place in the Sainsbury Wing.
"The Gallery's aim has always been to make sure its collection is on display at all times but from time to time paintings have to be moved for a number of reasons."
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