Chambers is expected to go to the High Court this week to challenge the BOA's lifetime ban triggered by his positive test for the designer steroid THG.

The BOA, who have a by-law imposing life bans on any athlete who fails a drugs test, have responded by supporting a petition initiated by the British Athletes' Commission.

The petition says: "The core foundation of the Olympic Movement is its values of fair play, respect and friendship.

"As Olympians we are the custodians of those ideals and any athlete who has taken performance enhancing drugs has not respected their worth.

"The highest accolade for any athlete is to be an Olympian and we believe that allowing drug cheats the privilege of competing at the Olympic Games for Team GB is wrong."

Chambers, whose two-year ban expired in 2005, clocked 10.06 seconds in the 100m at a meeting in Germany on Saturday, well inside the British Olympic team's qualifying mark. That is step one of an attempt to reach Beijing with step two likely to take him into the courts.

The BOA have not received any proceedings from Chambers' lawyers but issued a statement following Saturday's run.

The statement said: "As we have made very clear, the BOA will vigorously defend any case that comes to us which is challenging our eligibility by-law.

"In the interests of the British Olympic Movement and the athletes who aspire to line up at an Olympic Games and our youngsters looking for Olympic glory in London, the BOA confirms that it will vigorously and unequivocally defend its lifetime ban on drug cheats who have brought themselves and their sports into disrepute."