NEW YORK — Vincent van Gogh’s “Portrait of Dr. Gachet” sold for $82.5 million Tuesday, a world auction record for any art work and double the price estimated by Christie’s, a spokeswoman for the auction house said.

“This is by far the world’s most expensive painting,” surpassing the $53.9 million price bid for van Gogh’s “Irises” in November 1987 at Sotheby’s auction house, said Christie’s spokeswoman Susan Britman.

The buyer, a representative of the Kobayashi Gallery in Tokyo, was in the room during the approximately 10 minutes of bidding that opened at $20 million, said Britman. Toward the end of bidding, just the Kobayashi representative and a telephone bidder were vying for the painting, she said.

“Two people were determined to have a great picture,” said Christopher J. Burge, president of Christie’s auction.