The pulling power of the 2012 London Olympic Games has earned British athletics a mammoth £50million sponsorship - but athletes will have to sign central contracts to qualify for the extra funding.

The biggest deal outside football in British sport was announced today with long-term sponsor, Norwich Union, unveiling a new agreement to back the sport through to 2012.

However, in order to benefit from lottery funding and the Norwich Union backing, Britain's star performers will have to agree to contracts.

This will mean committing to a programme of events, including taking part in trials, championships and British televised athletics meetings rather than chasing money by competing around the world.

Dave Collins, the performance director of UK Athletics, confirmed funding could be withdrawn in cases of athletes failing to deliver, both in terms of performance and commitment, describing it as a "a two-way thing."

Collins said: "This is all about development. It's the lifeblood of the sport.

"Somewhere out there is the next Dean Macey. We need to take that young athlete and develop his skills all the way up to Olympic level.

"We will be able to provide more athletes with personal coaches and take more coaches out early to the training camps in Beijing before the 2008 Olympics."

The Norwich Union money will also be targeted at producing athletes and coaches through schools and grassroots programmes.

The estimate is that more than 10 million children will be involved in grassroots schemes by 2012 with training being provided for 100,000 teachers to supervise athletics in 5,000 secondary and 20,000 primary schools.

The additional backing - described by Collins as a "tremendous value" - was welcomed by Macey, the decathlon gold medal winner at last month's Commonwealth games in Melbourne, who has no problems with signing a central contract.

He said: "Norwich Union's continued and increased support for athletics means that the British team will be able to receive the best possible preparation support for major championships.

"Athletes like myself will have an excellent programme of domestic meetings to check our progress against the best in the world on home soil."

Macey, who returned from a series of major injuries to triumph in Melbourne, added: "It will enable us to have some of the best medical teams behind us.

"That's a major part of me getting on the starting line healthy and if I get on the line healthy I'm dangerous."

Kelly Sotherton, winner of the heptathlon gold in Melbourne, also backed the idea of central contracts.

"It's a good way of continuing what we do and making sure we peak at the correct time going to the major championships. It's no good peaking at trials or at Crystal Palace; you want to perform to win medals.

"Also, if we are injured and not competing, we are going to get paid so it takes away that worry," she said.

Sotherton, a late developer who is aiming for an athletics swansong at the London Olympics when she will be 35 years old, admitted: "I wish this had been around when I was starting out.

"I know what it's like to have to train alongside a 9-5 job but this will enable athletes to concentrate 100% on aiming for medals."

The sponsorship was announced at the new Mile End Sports Centre, opened last month in East London, which will be home to the 2012 Olympics.

Dave Moorcroft, chief executive of UK Athletics, said: "We've been thrilled with the support Norwich Union has given athletics since 1999 and are delighted they are to continue the partnership.

"The current crop of very talented juniors is testament to the long-term foundations provided at grassroots level and, due to Norwich Union's long-term commitment announced today, the sport will be able to build on this platform by boosting participation, increasing the talent pool to prepare future champions to reach our medal targets in 2008 and 2012."