Art prices continued to rise ever higher at the big contemporary auctions in New York this week, defying warnings from dealers and collectors that the top of the market had already been reached.

Sotheby’s, Christie’s and Phillips together sold $1.7bn (€1.2bn, £828m) in Impressionist, modern and contemporary works of art in the past two weeks – well above last year’s $1.3bn, and more than twice the amount of two years ago. The strong results were achieved even as financial markets remained in turmoil.