Andy Parkinson, the acting director of Drug-Free Sport, said: “By the end of Beijing we will see that there have been positive tests during both the Olympics and Paralympics – we would be naïve to think they would be a totally clean Games.

 

"Indeed, from an anti-doping perspective, if they were totally clean, particularly given the current climate, you might even say that the system has failed those athletes who are competing drug-free.”

 

Parkinson's comments came the day after John Fahey, the chairman of the World Anti-Doping Agency, claimed that Beijing would be the cleanest in history.

 

Parkinson said: “We have to acknowledge, as do the public, that there will be positive tests in the future but that this isn’t necessarily a bad thing for anti-doping as it actually demonstrates that we are catching the cheats.”

 

Parkinson's warning came on the day that UK Sport published its results from the first quarter of its 2008/09 National Anti-Doping Programme.

 

The results issued today by UK Sport cover the period from April-June 2008 during which time over 2,000 tests were carried out across 42 sports.

 

This includes pre-Games tests on British athletes heading for Beijing.

 

Governing bodies receiving most tests were the Football Association (400), UK Athletics (196), FINA (176), the Amateur Rowing Association (158) and British Cycling (158).

 

Of the 65 possible anti-doping violations covered by the report, 25 were concluded as "no case to answer".

 

Of the five involving anabolic steroids the most serious offence was by Fathi Meftah, an Algerian who tested positive at the World Cross Country Championships in Edinburgh in March.

 

He has been suspended by the International Association of Athletics Federations for two years.