The pulling power of the 2012 London Olympic Games has earned British athletics a mammoth #50 million 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 yesterday 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Dave Collins, the performance director of UK Athletics, confirmed funding could be withdrawn in cases of athletes failing to deliver, both in terms of performance and commitment, describing it as a "a two-way thing."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.

"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 grass-roots programmes.

The estimate is that more than ten 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.

Birchfield Harrier Kelly Sotherton, winner of the Commonwealth Games heptathlon gold in Melbourne, 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," she said. "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 nine-to- five job but this will enable athletes to concentrate 100 per cent on aiming for medals."

Dave Moorcroft, chief executive of UK Athletics, said: "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."