Russia has agreed to lend the Royal Academy of Arts some of its most treasured paintings, but it took a “letter of comfort” signed by the British Government to reassure the Russians that everything would be returned.

The Royal Academy will show more than 120 works by French and Russian artists, many of which have never been seen outside Russia. The star of the blockbuster exhibition is set to be The Dance by Matisse.

Securing such an important loan was particularly difficult because many of the works were nationalised after the Russian Revolution in 1917 and have been the subject of legal claims by the collectors’ heirs.

Negotiations were taken to the highest levels, with Gordon Brown and President Putin each giving their support. But without the “letter of comfort”, which states that the Government will not support any attempt to seize or impound a work on loan, the exhibition could not have gone ahead.

Russia announced that it would no longer lend any of its works to countries without antiseizure laws after 55 paintings held by the Pushkin Museum of Fine Arts in Moscow were impounded in 2005 while on loan to Switzerland. The seizure was the result of a financial dispute between a Geneva trading company and the Russian State, although the works were released days after the Swiss Government intervened.

André-Marc Delocque-Fourcaud, grandson of The Dance’s original owner, Sergei Shchukin, has also tried to retrieve works held by the Russian State, lodging unsuccessful claims in Paris, Rome and Los Angeles, but he is said to have ended his action in 2004.

Britain is one of the few European countries without an antiseizure law – although one is going through Parliament – which is why it took such a strong commitment from the Government to secure the loan. Four years ago, the Hermitage Museum in“ St Petersburg refused to lend Titian’s Saint Sebastianto the National Gallery in London.

The Royal Academy is hoping to attract hundreds of thousands of visitors to From Russia: French and Russian Master Paintings 1870-1925and believes that the show will be as popular as its record-breaking Monet exhibition.

The show, which opens in London in January, will explore the links between French and Russian art during a period which included some of the most important developments in modern art, including Impressionism. Some of the greatest works by Renoir, Cézanne, Van Gogh and Gauguin will hang alongside those by Kandinsky, Malevich and Chagall.

Visitors will be able to see how Kandinsky drew on Russian fairytales as a starting point for his daring experiments in abstraction, and how Chagall adapted elements of Cubism for his highly individual interpretations of Russian-Jewish folklore.

The exhibition will also illustrate Russia’s rich history of collecting. Like the Russian billionaires of today, who have caused a stir on the international art market by buying works for record amounts, men such as Shchukin and his fellow Moscow textile merchant Ivan Morosov built up impressive collections. They scoured Paris for Impressionist and PostImpressionist works, buying paintings that are today revered as masterpieces but which were, in their day, considered “cutting-edge”, the Royal Academy said.

Shchukin became Matisse’s greatest patron, commissioning The Dance (1910) as part of a bold scheme to decorate the grand staircase of his Moscow mansion.

Sir Norman Rosenthal, exhibitions secretary of the Royal Academy and the show’s co-curator, said: “ The Dance, which is about four metres by three metres, will be perhaps the most sensational highlight of the exhibition. It was commissioned at a time when Matisse’s work was largely misunderstood. It was an extraordinarily radical and large-scale painting.”

A correspondence between the two men shows that Shchukin got cold feet and nearly cancelled the commission because of the painting’s boldness and nudity. He feared that it would be too shocking for bourgeois society and his daughters. But he changed his mind, saying that he was as brave a collector as Matisse was a brave painter.

The exhibition – for which The Times is the media partner - will be at Burlington House from January 26 until April 18.

— To book tickets in advance, visit royalacademy.org.uk or call 0870 8488484.

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