Cover David Hockney, 'Sur la Terrasse' (1971) © Image Courtesy of Christie's

Sur la Terrasse by David Hockney will go on sale as part of Christie's Post-War and Contemporary Art evening sale.

Hockney began this previously little-seen painting in March 1971, at a time when his relationship with his lover and greatest muse Peter Schlesinger was declining.

Sur la Terrasse, which marks the British painter's last depiction of Schlesinger during their time together, is based on a series of photographs taken on the balcony of the couple's room at the Hôtel de la Mamounia in Marrakesh.

This portrait depicts Schlesinger on a life-size scale as he stands with his back to the artist, staring away with detachment into the jungle-like landscape of the Moroccan city.

Sur la Terrasse will hit the auction block for the first time on November 13 after remaining in the same private collection for nearly half a century.

It is estimated to sell between US$25 million and US$45 million, which positions the colourful portrait as a likely highlight of Christie's Post-War and Contemporary Art evening sale.

Although Sur la Terrasse has never appeared on the market before, its high pre-sale estimate is far from the British painter's current auction record.

Last November, Hockney became the most highly valued living artist when his Portrait of an Artist (Pool With Two Figures) sold for $90.3 million at Christie's New York.

He was dethroned six months later by Jeff Koons, whose Rabbit fetched $91.1 million at Christie's New York.

"We are very pleased to be bringing Sur la Terrasse to market and into the public eye after residing within a private collection for nearly 40 years, where it went unseen by the public for almost as long," Ana Maria Celis, who is the Head of Christie's Evening Sale, Post-war and Contemporary Art, said in a statement.

Additional highlights of Christie's Post-War and Contemporary Art sale include Ed Ruscha's Hurting the Word Radio #2, estimated between US$30 million and US$40 million; Pablo Picasso's Buste d'homme, estimated between US$9 million and US$12 million; and Frank Stella's Gray Scramble IX (Single), estimated between US$2 million and US$3 million.

See also: This Yoshitomo Nara Painting Sold For HK$196 Million At Sotheby's Hong Kong