Team Sky, home of Tour de France winner Bradley Wiggins, has reiterated its zero-tolerance stance on doping after a day which saw Lance Armstrong become increasingly isolated.

In the wake of the damning United States Anti-Doping Agency (USADA) report into the activities of Armstrong's United States Postal Service team, Team Sky will ask every rider and member of staff to sign a statement to confirm they have never been involved in doping.

"Should anyone choose not to sign up to our clear policy they will have to leave the team" - Team Sky

A statement from the British team read: "There is no place in Team Sky for those with an involvement in doping, whether past or present. This applies to management, support staff and riders.

"Over the coming weeks, we will talk individually with each team member and ask everyone, at every level of the team, to sign up to a clear written policy, confirming that they have no past or present involvement in doping.

"Should anyone choose not to sign up to our clear policy they will have to leave the team, as will anyone who does sign but is subsequently found to be in breach."

Team Sky principal Dave Brailsford informed his charges of the policy on the first day of the end-of-season camp.

Canadian rider Michael Barry was one of 11 riders who testified against Lance Armstrong to the USADA, who have accused the US Postal team of running "the most sophisticated, professionalised and successful doping programme that sport has ever seen".

Barry, who spent three seasons with Team Sky before retiring last month, admitted to doping earlier in his career in giving evidence to USADA.

Team Sky sports director Sean Yates worked with Armstrong at the Motorola and Astana teams, but has denied any knowledge of doping.

Australian Michael Rogers, a key member of the Tour-winning team, worked with disgraced doctor Michele Ferrari, implicated in the USADA report, earlier in his career but also denies using performance-enhancing drugs.

Armstrong, who won the Tour from 1999 to 2005, did not co-operate with the USADA investigation and maintains his innocence.

He stepped down as chairman of his cancer charity, Livestrong, yesterday.

"To spare the foundation any negative effects as a result of controversy surrounding my cycling career, I will conclude my chairmanship," said Armstrong, who will be succeeded by vice-chairman Jeff Garvey.

Sponsors also severed ties with the Texan.

Nike, Anheuser-Busch and Trek bikes announced they would no longer work with Armstrong, but will continue to support the Livestrong Foundation.

Oakley, meanwhile, are considering their position.