The Garcon a la Pipe. (Reuters)

It is likely to become the most expensive work of art in history. Art experts believe that the “hauntingly beautiful” painting by Picasso of a boy with a pipe will be sold for as much as $100 million when it is auctioned this week.

The portrait, Garcon a la Pipe, which was painted by Pablo Picasso in 1905, will be auctioned at Sotheby’s in New York on Wednesday. The auction house has publicly given a pre-sale estimate of $70 million to the work, which was bought for $30,000 in 1950 and is now being sold to raise money for charity. That would make it the fifth most expensive work of art ever.

In private, however, officials are confident that the price will surpass the record $82.5 million paid by Ryoei Saito, a Japanese paper manufacturer, for The Portrait of Doctor Gachet by Vincent Van Gogh in 1990.

John Richardson, an art critic who has written a biography of Picasso, said he expected the painting to sell for a record price. “It may not be the most important painting in the world, but I have no doubt that it will be the most expensive,” he said. “It only takes two people keen on buying the painting to send the price sky high and I already know one person who is prepared to pay at least $100 million to secure it.”

Paintings by Picasso have sold extremely well at auction. Nine of the 20 most expensive paintings sold have been by the artist. Four years ago, a painting from his Blue period fetched $55 million at Christie’s, New York. The work — Femme aux Bras Croises — was sold for twice the pre-sale estimate.

Charles Moffett, the co-director of Impressionist and Modern Art at Sotheby’s, said: “In my view this (Garcon a la Pipe) is a far superior work. It is more engaging and would have a wider appeal than many of the Picassos that have come on the market in recent times. “It is within a small category of pictures that could easily fetch $100 million without surprising anyone. It is impossible to say how high the bidding will go on this painting, that is why we have placed an ‘in-excess-of’ estimate rather than a price range as is usually the case.”

Painted soon after the 24-year-old Picasso settled in Paris, it depicts a young Parisian boy holding a pipe in his left hand and wearing a garland of flowers. Moffett said it was “without question, one of the most important early works by Pablo Picasso ever to appear on the market”.

He added: “The painting emits a feeling of lost innocence and typifies the melancholy charm of Picasso’s Rose period. The subject seems to be in deep reflection, life is both exciting and yet daunting and full of perils. It is a hauntingly beautiful painting. Part of the allure of the painting is that we don’t exactly know what is going on. We are not exactly sure of the relationship of the boy to Picasso, but know that he appears several times in Picasso’s art at that time.”

The boy has been identified as “p’tit Louis”, who often loitered around the Bateau Lavoir in Montmartre, where Picasso lived and worked. Writing 50 years later, he described the boy as one of his most regular visitors.

The painting was bought by John Hay Whitney, a former American ambassador to Britain, and his wife, Betsey, in 1950. It was added to a collection begun by his parents, the heirs to a fortune made from oil, tobacco, railways and property development. The painting remained in the Whitneys’ private collection until it was bequeathed to the Greentree Foundation, a philanthropic organisation created by Mrs Whitney in 1982 after the death of her husband. She died in 1998 and left much of her property to the foundation.

The painting has appeared in exhibitions at the Museum of Modern Art in New York, the Museum of Fine Arts in Boston and the National Gallery in Washington. It was also displayed at the Tate Gallery in London in 1960 and 1961, but has spent most of its life on the wall of a private house.

Among those rumoured to be interested in acquiring it are Bill Gates, the founder of Microsoft; Ronald and Leonard Lauder, the heirs of the Estee Lauder cosmetic company; and Steve Wynn, the casino owner.