Difficulties in securing planning permission were responsible for the decision.
The site was to have been Britain's largest single-venue leisure destination in the UK, with up to 3.5 million visitors a year. Currently, Alton Towers in Staffordshire is the biggest, attracting just over 3 million visitors a year, although Blackpool Pleasure Beach draws in 7 million annually.
Both parties say they are committed to finding another site, while Hillingdon Borough Council has offered to try to find a replacement venue.
The news is a set-back in the short term, however, for United News' aspirations to develop a broad spectrum of media-linked businesses.
Movie World, as well as housing the first new film studio to be built in Britain since the end of the Second World War, would have featured white-knuckle rides like the "Batman roller-coaster". With its vast film and TV studios, the project would have created 900 permanent jobs, and an estimated 3,500 more through knock-on trade. It was expected to contribute pounds 173m to Britain's balance of trade figures.
It would also have been the first big challenge to DisneyLand Paris, bringing the concept of the American theme park to the UK.
Terry Ilott, director of public affairs for Movie World, said: "It's a disappointment - and a relief. A disappointment after all the time and effort, but a relief to have found out at this early stage the project was unworkable at this site."
Although Hillingdon was the best site for Movie World, Warner and its advisers are already looking at other sites, including ones between Birmingham and London. "There are lots of disused airfields and the like, which could provide a suitable alternative to Hillingdon," said Mr Ilott.
The problems revolved around existing users of the 150-acre site. Warner found an alternative site for the Middlesex County Show three miles away, which would have cost millions to develop properly, but replacing some of the existing leisure facilities on the site proved a more intractable problem.
Warner promised to build a pounds 4m sports centre, with an indoor swimming pool, at Uxbridge College. As part of the deal, however, Uxbridge College insisted on an extra classroom block as well.
Meanwhile, the council was unwilling to accept the sports complex as its own asset. This was because the sports centre would have been counted as a capital receipt, and for every capital receipt, a council must reduce its debt by 50 per cent of the value of the receipt.
This would have meant Hillingdon finding pounds 2m in cash to reduce its debts - money it was reluctant to put up. Nor did Warner want to own and manage a local sports facility as part of its obligation to the council.
"In the meantime," said Mr Ilott, "costs were ratcheting up, and we found that if we pursued this through the expense of a public inquiry, we would be unable to meet our return-on-investment targets."
One site being examined by Warner is close to the M1. It was initially rejected when a search began in 1994, because the Department of Transport planned to reduce the road at that point to single-lane traffic for lane widening to be carried out. However, the improvements are no longer to be made, and Mr Ilott said the joint venture would look at the site again, along with others.
Earlier this week, Warner signed up as a tenant in a pounds 500m redevelopment of Battersea Power Station in south London. With its partner, the Australian media company Village Roadshow, it will build a multi-screen cinema complex. The pull-out from Hillingdon, however, represents a temporary set-back for the UK film industry, which has recently been on a roll. It is, however entirely in the tradition of an industry famous for disappointing its followers.