The works are on loan from the Hermitage Museum in St Petersburg and other Russian museums, as well as the National Gallery in Washington and the Metropolitan Museum of Art in New York.

BBC: BP brings old masters back to Britain after 234 years

High-profile Russian and Chinese collectors have been buying art at auction or from galleries and then donating it to Russian and Chinese museums.

FORBES: The New Breed

Most such references, in textbooks and museums, vanished during the Sino-Russian conflicts of the 1960s.

FORBES: Issues & Ideas