London - International Olympic Committee presidential candidate Sergey Bubka urged athletics authorities to clamp down on drug cheats and increase the length of their bans.
The 49-year-old pole vaulting legend is backing fellow athletics great Sebastian Coe's recommendation that athletes who fail drugs tests be banned for four years instead of the current two-year sanction.
Bubka was speaking on Wednesday in the wake of a recent wave of high profile positive dope tests that have seen sprinters such as Asafa Powell and Tyson Gay sidelined and have damaged the credibility of the sport.
The Ukrainian is adamant bans must be longer if youngsters are to be attracted to track and field and the sport is to retain its integrity and that athletes must not hide behind the use of supplements if they fall foul of the drug testers.
"We will not excuse the dopers.
"It must be increased from a two-year ban to a four-year ban," Bubka told reporters.