The International Olympic Committee (IOC) today backed Britain's right to impose a hard-line lifetime ban to stop British drug cheats from competing at the London 2012 Games.
Denis Oswald, chairman of the IOC's co-ordination commission of inspectors, said he "respected the right" of each National Olympic Committee (NOC) to decide independently what behaviour is appropriate for athletes.
He said: "The autonomy of each National Olympic Committee is to establish their own policy on the eligibility of their athletes.
"It is not just about doping - it could be about gambling. This is something for the BOA (British Olympic Association) to determine."
A strong global spotlight has been shone on the issue after US 400m Olympic champion LaShawn Merritt yesterday overturned a ban against competing at the Olympics.
Merritt won a case in the Court of Arbitration for Sport (CAS) after challenging the IOC's controversial rule 45 that anyone banned for a doping offence for six months or more should miss the next Olympics - even if their suspension has expired.
The BOA's lifetime ban, which has been unsuccessfully challenged by sprinter Dwain Chambers, who has previous served a drugs ban, is even more draconian.
Speaking at the conclusion of a three-day inspection of London's preparations for the 2012 Games, Mr Oswald said: "It is in the Olympic Charter that the NOC has the right to establish the rules of eligibility of the athletes. We fully understand that the BOA has that rule and has had it for a number of years. It has been challenged but it stands and we respect the right of the BOA."
Merritt will now be able to defend his Olympic title. He was banned for 21 months in 2009 for failing a drugs test which he blamed on his use of an off-the-shelf penile-enhancement product.
London 2012 chairman Lord Coe said he backs "zero tolerance to drug use in sport and during the Games".
He described his personal opinion as "unreconstructed - I would go for a life ban".
At least 33 drug cheats from the United States alone who would have missed out on the London 2012 Olympics will now be eligible after the CAS yesterday declared the IOC ruling was "invalid and unenforceable".
The US anti-doping agency USADA lists 33 athletes who would have been prevented from taking part by the IOC - but who can now do so. These include Merritt.
Mr Oswald said the IOC was still studying and discussing the impact of the CAS ruling.
He said the ruling had not been in force at any previous Olympics or major championships and predicted there would be a "very limited" number of athletes headed for London 2012 who could be affected by it.
London 2012 was given another thumbs up by the IOC's co-ordination commission for its preparations for the Games.
This was the ninth and penultimate check-up before the Games begin in July 2012. Meetings and presentations have been held all week to update the inspectors.
They heard reports from London 2012, the British Government, the Greater London Authority, and Transport for London, as well as updates on areas such as services to the athletes, NOCs, International Federations, the media, the Paralympic Games and spectators, as well as updates on topics such as marketing, technology, culture, education and communications.
Mr Oswald said a lot of progress had been made since the last inspection six months ago in a range of areas including ticket sales, cultural events, volunteer recruitment and the 17 sport test events which have been completed over the summer.
Transport, given the huge demands that will be made on the old network system, remains an area that needs ongoing attention.
Mr Oswald said: "I can say that at this stage a lot of progress has been made and a lot of additional information has been given. This is a situation we will have to follow very cautiously until the end."