The exhibition, which includes Warhol's famous images of Marilyn Monroe, Campbell's soup tins and Chairman Mao, will be one of the largest staged in England. Dozens of David Hockney prints, from the artist's private collection, will also go on show.
Lord Archer, the best-selling novelist and a former deputy chairman of the Tory party, has been building his collection for seven years. For the past three years, he has employed five researchers to scour the world and find the finest examples of the artist's work. He now owns 317 oils and silk-screen prints, including 10 Marilyns, 10 Maos, 10 Campbell's soups, three Lenins, and four Ronald Reagans, plus images of Mick Jagger, Donald Duck and Mickey Mouse.
Although visitors to the Tory peer's penthouse apartment overlooking the Thames have seen examples of the distinctive paintings, next to work by Monet, Lowry and Picasso, nobody appears to have known about the extent of his interest in Warhol. Lord Archer said he had been fascinated by Warhol, but had decided to sell because he believed the value of the paintings was at a premium. Estimates put the Warhol collection at about pounds 25m, but at least one work could reach pounds 10m at auction. Last May, one of Warhol's Marilyn prints, "The Orange Marilyn", was sold at auction by Sotheby's in New York for pounds 10.6m - more than five times the expected price.
Lord Archer, who began collecting art 20 years ago, has hired a Bruton Street gallery for the exhibition, which begins on 20 October. Only 65 pieces will be shown at any one time. An exhibit likely to be viewed as one of the most interesting is the black-on-black silk-screen of Marilyn Monroe, which is valued at pounds 60,000.
The group of 83 signed Hockney prints, produced between 1952 and 1996, to go on show simultaneously, are from Hockney's private collection and will fetch from pounds 500 to pounds 16,000. The artist has always been reluctant to hold exhibitions in London, so the show is likely to attract intense interest.
However, it is the Warhol collection on which attention is mainly likely to focus. The American painter became a cult figure after his death in 1987, and his work has become increasingly fashionable in recent years.
Warhol opposed the elitism of art and disliked the idea that a painting was hand-made for the connoisseur. He favoured the silk-screen process, which allowed him endlessly to reproduce the same image, and he often chose to depict mundane household objects. Many collectors have become fascinated by his brightly coloured pieces and prices have soared.
Next month's exhibition has been organised by Lord Archer's dealer, Peter Gwyther, an expert on both of the 20th- century artists. Lord Archer said: "I have long been an admirer of Hockney and Warhol, and it has been a lifetime dream to bring them together. Hockney is probably England's greatest living artist and Warhol is unquestionably the great American draughtsman of the latter half of the century."