Sir Philip Green was among the billionaires and millionaires who descended on Sotheby’s in London last night to see one of Monet’s finest water lily paintings sell for £18.5 million.

Iconic masterpieces such as this come on to the market once in a lifetime, so excitement about such a “trophy painting” was inevitable.

Bidding began at £8 million and rose hesitantly. It stopped momentarily at £14.5 million before moving slowly up again.

Just as the auctioneer announced that it was selling for £15.5 million, someone pointed out yet another bidder in the room. The figure leapt to £16 million. There were quiet murmurings in the room as the collectors needed time to think. The Monet was finally bought by an Asian private collector who was in the room and on the telephone to someone else.

The figure fell short of Monet’s world record price, which has been held since 1998 for Bassin aux nymphéas et sentier au bord de l’eau of 1900. It sold at Sotheby’s in London for £19.8 million.

More than 600 collectors, curators and hangers-on crammed into the saleroom. The biggest collectors mostly hide their identity by bidding over the phone and, such was the level of interest last night, that as many as 40 phone lines had been installed. Sir Philip, the retail entrepreneur, was unusual in turning up.

Nymphéas of 1904, one of the first works in which Monet completely eliminated the horizon, to depict atmosphere and colour, paved the way for 20th-century abstract art.

About 45 works by most of the leading names of late 19th and 20th-century art were offered last night. Many had not been seen in public for years. The record was also broken for a Rodin sculpture, Iris, that had once belonged to Sylvester Stallone, the actor.

Although estimated at only £400,000 to £600,000, it sold for £4.6 million as one of only two lifetime casts to appear at auction. The previous record was £2.4 million.

Collectors bid furiously for Matisse’s Danseuse dans le fauteuil, sol en damier, of 1942. It went eventually to a telephone bidder, a European private collector for £10.99 million after seven minutes of bidding, against about ten for the Monet. When converted into dollars, the sale figure is $21.82 million, a record for the artist. The seller had bought it for £4.9 million seven years ago.

The sale totalled £80.39 million, against a low estimate of £56 million. Seventeen works sold for more than £1 million and five for more than £4 million. The prices confirmed London’s standing as the world’s booming art capital. Impressionist and Modern art sales in London have grown by 240 per cent since 2002, buoyed by money from Russian, Asian and Middle Eastern billionaires, as well as Wall Street and City bonuses.

This week’s sales of Impressionist and postwar art at Sotheby’s and Christie’s, which sold Monet’s Waterloo Bridge on Monday for £17.9 million, are expected to reach £450 million, another record for London.

Water works

200

Pictures of the water lilies

6

Water-lily pictures still in private hands

1.39m

Visitors to the Monet exhibition in 1999 at the Royal Academy, the most popular show ever

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