Andy Warhol's One Dollar Bill (1962) was the lead lot of Sotheby's contemporary art evening sale in London on July 1.

It realised £20.8m ($32.7m), an increase of 15.9% on an £18m ($28.2m) estimate.

Andy Warhol was obsessed with money and often used it as a symbol in his work

Warhol was obsessed with money and it appears as a motif throughout his work. He explained: "Money is the MOMENT to me. Money is my MOOD."

The lot was one of a series of works by Warhol displaying the dollar symbol that appeared in the sale. In all, the Warhol dollar collection made £34.3m ($53.9m).

An important self-portrait by Francis Bacon sold for £15.2m ($23.7m), while David Hockney's Arranged Felled Trees made £3.3m ($5.1m).

The auction realised total sales of £130.3m ($203.4m) - a new record for a sale held by Sotheby's in Europe.

Alex Branczik, Sotheby's head of contemporary art in London, comments: "We reached new heights at Sotheby's tonight with the highest total we've ever achieved for Contemporary Art in London.

"Bidders from across the globe were drawn to Warhol works that ripped up the rule book for 20th-century art; rediscovered Francis Bacon gems; and some of the greatest works by British artists of the last 70 years.

"Tonight's achievements affirm the pivotal position of London within the international art market."

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