UK Athletics has failed in a bid to prevent disgraced sprinter Dwain from competing in the Norwich Union World Indoor Trials and National Championships in Sheffield this weekend.

UK Athletics has failed in a bid to prevent disgraced sprinter Dwain from competing in the Norwich Union World Indoor Trials and National Championships in Sheffield this weekend.

The sport's governing body announced they had sanctioned Chambers' participation, with the athlete's Leeds-based solicitors Ford & Warren ready to apply for a High Court injunction if he had been refused permission to compete.

UKA chief executive Niels de Vos expressed his disappointment at the outcome of extensive legal deliberations, which have left the sport legally unable to refuse to offer Chambers a place in the 60 metres race on Sunday.

"I believe that the BALCO scandal and the recent imprisonment of Marion Jones have significantly damaged the credibility of athletics as a sport," said de Vos, who is determined UKA will pursue a strong anti-doping policy in the future.

"To maintain the public's full confidence in our athletes and in the sport in general we want to ensure beyond doubt that all athletes wishing to compete under the Union flag are drug-free.

"Our view is that all established athletes must participate in the out-of-competition testing programme for a continuous 12 months prior to competing for GB. Dwain is not in that position.

"However, we recognise that we do not have sufficiently strong legal grounds to refuse him an invitation given our published invitation policy.

"Reluctantly therefore, Dwain Chambers has been informed he is permitted to participate.'

However, it is almost certain Chambers will have to win on Sunday to guarantee a place in the world indoor championships in Valencia from March 7-9.'

Chambers had served a two-year ban after testing positive for designer drug THG and decided to return to athletics after failing in a bid to carve out a new career in American football.

He returned to action last weekend where he achieved the qualifying time and won the 60m at the Birmingham Games, meaning he was entitled to run in Sheffield under UKA's own selection policy.