Works by Lucian Freud and Francis Bacon -- the British artists whose paintings sold for record prices last week in New York -- are expected to fetch at least 10 million pounds ($19.6 million) each at Christie's International's June 30 sale of contemporary art in London, the auction house said.Freud's 1980 canvas, "Naked Portrait With Reflection",showing a nude model reclining on a battered sofa with the artist's legs seen in a mirror beyond, has an upper estimate of 15 million pounds, Christie's said today in an e-mailed statement. Bacon's 1975 trio of 14 inch-by-12 inch canvases, "Three Studies for a Self-Portrait,'' may sell for more than 10 million pounds. "Bacon and Freud have always been expensive because their works are actually quite rare,'' said Gerard Faggionato, the London-based dealer who represents the Bacon estate. "Russians are interested in them and there are far more American collectors than there were five years ago.''Bacon and Freud were close friends in the 1950s and 1960s, but later fell out. The duo made headlines at New York's art auctions last week when Freud's 7 foot-wide 1995 nude painting of the dozing 280-pound civil servant Sue Tilley "Benefits Supervisor Sleeping'' fetched $33.6 million, the most expensive work by a living artist at auction. A day later, Bacon's "Triptych, 1976'' sold for $86.3 million, the priciest contemporary artwork sold at auction.Abramovich's HomeThe Art Newspaper said on its Web site that "sources close to the market'' said both paintings were bought by Roman Abramovich, the owner of English Premier League football side Chelsea, possibly for display in his London home. "Because of international demand for these artists, quality is coming out,'' said Pilar Ordovas, Christie's head of postwar and contemporary art, in a telephone interview. "And because quality is coming out, prices remains strong.''The gains have been phenomenal. According to Artnet.com, which tracks salesroom results, the 2005 auction record for Bacon was $10.1 million and for Freud, $7.7 million.Freud's 3 foot-square "Naked Portrait'' last appeared at auction in December 1998 when it fetched 2.8 million pounds, said Christie's. The Bacon triptych, bought by its seller in 1976, has never been seen in public or offered at auction.Christie's said the owners of both works to be offered next month have been guaranteed minimum prices.