Bridget Jones fans are eagerly awaiting the film's sequel

Much of this money has come from overseas investment, with Hollywood contributing a huge amount to make their films in the UK.

The 85% increase in overseas spending, up to �409m in 2003, can be attributed to several factors.

One of these is the growing popularity of DVDs, which have sparked demand for an ever-growing and quicker turnaround of film releases, which has also reduced the gamble for film-makers.

"It has been reduced by massive sales and revenues of the DVD format which has reduced the risk, particularly for the Hollywood studios where DVD revenues are outstripping box office gross figures," former TV executive Michael Grade, who now runs Pinewood and Shepperton Studios, told BBC Breakfast.

Another reason for the boom year is the wealth of creative and technical talent available to foreign productions who choose to set up camp in the UK.

Reputation

It is estimated there are nearly 1,000 firms working in the post-production sector, providing sound, music or graphic effects.

The industry itself supports about 15,000 jobs, and has a world-renowned reputation, ranking alongside its US counterpart.

Nik Powell, director of the National Film and Television School, said that despite the large numbers of big productions currently on UK soil, including Troy, Alexander and Thunderbirds, none of these would suffer from a lack of skilled personnel.

"We are one of the few countries in the world that can support a huge range of film-making at the same time," he said.

Another reason for the significant increase in investment is the tax breaks offered to film-makers to bring their productions to the UK.

The tax breaks are available to films that are classed as British or are co-produced by Britain.

But there have been concerns that the tax relief rules are being manipulated, and not all those receiving dispensation are entitled to it.

Gordon Brown is to overhaul the tax break system for British films

And Chancellor Gordon Brown has already announced plans to scrap the enticing tax relief in June 2005.

This has sparked worries that Hollywood investment could be taken elsewhere where relief is offered, such as Ireland.

Fickle

Although Mr Brown has pledged to support the industry he has not given specifics of a replacement.

Another fear is the continued strength of the pound against the dollar which could mean costs go up in the coming year, therefore leading to fall in American production coming to the UK.

UK Film Council chairman Sir Alan Parker also fears that the staggering increase in investment may also be difficult to maintain in such a notorious fickle industry.

"Whether it is sustainable, I don't know," Sir Alan told BBC Breakfast.

"I think its a very high figure and to keep it going that much is going to be difficult."

But although many of the films made in the UK cannot be credited as British films, the outside investment should have a positive knock-on effect for home-made movies.