Love Among the Ruins, a long unseen masterpiece by British pre-Raphaelite artist Sir Edward Coley Burne-Jones (1833-1898), is to auction at Christie's on July 11.
The intensely romantic oil on canvas, which features a pair of lovers seemingly lost in rapture, is dated 1873, and is expected to achieve between £3m ($4.5m) and £5m ($7.5m) at the London auction.
Peter Brown, Christie's director of Victorian pictures, comments: "The market for Victorian art has expanded and seen increased international bidding from the US, Russia and Asia.
"Following the success of the pre-Raphaelite exhibition at the Tate London, which has opened in Washington before it moves to Moscow in June 2013, there could not be a more propitious time to bring this picture to the market."
Works by Burne-Jones have previously proved popular at auction. The artist's A Sea Nymph brought £1.1m ($2m) to Christie's when it sold in June 2005.
Christie's Harriet Drummond calls Love Among the Ruins "one of the most important works by the artist ever to come to auction", stating that the painting is "arguably the artist's most Italianate, most intensely romantic, beautiful and significant work to remain in private hands."
The painting was last bought in 1958 for 480 guineas (about £500).
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