Competitors from Russia and Kenya will need to have extra checks before they are allowed to compete at Rio later this year, the International Olympic Committee (IOC) has agreed.
The Committee met on Tuesday to discuss a five-point anti-doping plan.
One of the points agreed was that "the presumption of innocence of athletes" from Russia and Kenya was "being put seriously into question" because they are non-compliant with the World Anti-Doping Code.
As a result, every international sports federation should decide the eligibility of these athletes "on an individual basis to ensure a level playing field in their sport".
The IOC also said "the absence of a positive national anti-doping test should not be considered sufficient" to prove innocence, and that additional testing systems should be taken into account when assessing the athletes.
The IOC has already banned the Russian field and track team from competing in this year's Olympics, due to state-sponsored doping.
Other points agreed during the meeting include:
- Encouraging international federations and national Olympic committees to "keep doped athletes away from the Olympic Games Rio", and "take swift action to suspend all athletes who have infringed anti-doping rules"
- Respecting the decision to uphold the ban on the Russian field and track team
- Encouraging international federations and national Olympic committees to not just sanction athletes, but also "their coaches, officials, doctors or any other persons implicated"
- Reviewing the anti-doping situation with an "Extraordinary World Conference on Doping" next year