BUDAPEST, Hungary — Russia and Iran are among several nations who will lose places in the next Olympic weightlifting competition because of years of doping.

The International Weightlifting Federation has published new rules which limit countries to one male and one female entry at the 2020 Tokyo Olympics if they have had more than 20 doping cases in the sport since July 2008.

That applies to Russia, Kazakhstan, Azerbaijan, Armenia and Belarus, all major weightlifting powers. The IWF could still decide to ban them entirely if more cases emerge, IWF spokeswoman Lilla Rozgonyi said.

India and Iran fall into a second category of nations with between 10 and 20 confirmed doping cases in that period. Those countries can enter a maximum of two men and two women.

Other countries can enter up to four men and four women for the 2020 Games.

Weightlifting's Olympic place came under threat after retesting of samples from the 2008 and 2012 Games revealed 49 doping cases. In one event from 2012, six of the top seven finishers were disqualified.

After those cases emerged, the International Olympic Committee reduced the size of the weightlifting competition for the 2020 Olympics. The new rules are a way of ensuring the countries most to blame for weightlifting's predicament pay the heaviest price.

The new code of rules was "approved by the IOC and follows the logic that the IOC quota reduction ... was a 'consequence' of the retests from 2008 and 2012," Rozgonyi said.

The new rules also force athletes to compete in at least six major events in the 18-month Olympic qualifying period. In the past, some lifters have barely competed ahead of the Olympics, leading to suspicions they were avoiding doping tests.

Russia was banned entirely from weightlifting at the 2016 Olympics after the IWF ruled its team's persistent steroid use had tarnished the sport's image. Nine countries, including Russia and China, were barred from last year's world championships because of doping.