Christie's auction house in London hopes to raise more than 57 million pounds at an upcoming auction of Post-War and Contemporary Art auction. As banks go bust and the world's stock markets reel, Christie's unveiled the works that are up for grabs. The auctioneer hails the collection as the most valuable and comprehensive autumn sale ever.

The headline lot is Lucian Freud's last remaining portrait of his great friend and fellow British artist, Francis Bacon. The other portrait was stolen from a Berlin exhibition in 1988.

The portrait of Bacon is unfinished. It offers a glimpse into the inspirational relationship between two great British artists of the 20th century. The painting has been in private hands since 1970 and has been exhibited only twice.

Judd Tully, editor-at-large of Art And Auction Magazine, said, "It's an important work, it's rare, it has all of the bells and whistles that one would think that given the estimate it would reach. However given the time that we are in right now, no-one really knows. This week is going to be a huge, I don't know about huge, but an acid test for the art market."

The Freud is expected to fetch between five and seven million pounds.