A record 1,500 drugs tests will be carried out on British athletes preparing for the Beijing Olympics, the national anti-doping agency announced today.

UK Sport have increased the number of tests by 30 per cent compared to the last Games and competitors in "high-risk" sports such as athletics, swimming and cycling can expect to be asked for blood or urine samples up to five times over the next four months.

Tests, both during events and out-of-competition, will be carried out on around 250 potential Olympic athletes, plus the same number due to compete in the Paralympics.

In the highly pressured pre-Games period not a single British athlete will go untested as the agency attempt to repeat the experience of the Athens Games, when no member of Team GB tested positive.

Beijing gold medal hope Christine Ohuruogu served a one-year ban for missing three out-of-competition drug tests. She returned to win the World Championship 400metres title and then won her appeal against a lifetime ban imposed by the British Olympic Association.

The stricter testing regime confronting athletes will be continued in China when it becomes the responsibility of the International Olympic Committee, which has pledged to carry out a record 4,500 tests during the Games.

John Scott, director of Drug-Free Sport at UK Sport, said: "We want the British public to have confidence that the performances they are watching are from athletes who have achieved success through four years hard work, determination and dedication and not through cheating."

UK Sport, the quango also responsible for elite performance, will be carrying out drugs testing for the last time prior to an Olympics before the role is taken on by the embryonic National Anti-Doping Agency.