“A spectacular sale of Russian art was cancelled last night, on the eve of the London auction, when a Russian billionaire stepped in to buy the entire collection of the late musician Mstislav Rostropovich, promising to return it to Russia. Alisher Usmanov, the 18th richest man in Russia, is believed to have paid more than £25m, well above the highest estimate of £20m, to stop the sale. Sotheby’s, which initially refused to identify Mr Usmanov, later confirmed his name when the Russian news agency Interfax identified him.”