Over half of the 377 weightlifters at the world championships that begin on Tuesday in the United States will be drug tested as the sport begins a new chapter to try to retain its Olympic status after decisions taken by the governing IWF.

By the time of the last lift on Dec 5 at the worlds in Anaheim, California, the International Olympic Committee (IOC) will have begun deliberations on whether weightlifting should feature at the Paris 2024 Games.

"We accept that in the past the incidence of doping in weightlifting has been too high," says Hungarian Tamas Ajan, president of the International Weightlifting Federation (IWF) since 2000 and secretary general for 24 years before that.

Ajan, 78, was speaking in Anaheim at the weekend, where the IWF adopted a hardline approach to doping at an executive board meeting. It will target "less than a dozen high-risk countries where there is an entrenched culture of doping that goes beyond weightlifting". The countries involved were not named.

Of the 49 weightlifting positives in the re-testing of samples from the 2008 and 2012 Olympics “ more than any other sport - 43 were from nations formerly part of the Soviet Union.

Russia was banned from the Rio 2016 Games for repeated offences that "brought weightlifting into disrepute" and is also among the nine nations excluded from the world championships for having three or more of those 49 positives.

Russian Weightlifting Federation president Maxim Agapitov said at the European Junior Championships in Albania on Oct 22: "We are building a new future, but I accept we have to take responsibility for so many positives in the past. It is in the past but it so happens that we must answer for it."

China is also banned from the world championships in Anaheim and, like Russia, has been accused of state-sponsored doping.

When the IFW said it was imposing a one-year ban on Chinese lifters from mid-October, the Chinese Weightlifting Association (CWA) issued a statement expressing "regret" at the decision.

"China has been firmly against doping and has a zero-tolerance approach to this particular problem," Xinhua reported the CWA as saying in a statement on Oct 1.

Doping allegations against China and Russia are under investigation by the World Anti-Doping Agency (WADA).

However, Russia, like the Chinese, has always denied any involvement in state-sponsored doping.

Under new rules approved by the IWF on Saturday, countries will face bans of up to four years "if they do not fulfil their anti-doping responsibilities", which would keep them out of the Olympics.

A new Olympic qualifying system will also require athletes to compete more often than some do now.

Kazakh Ilya Ilyin, stripped of his gold medals from Beijing and London after testing positive, was absent from international competition for more than two years between those two Games.

There will be more out-of-competition testing, and a more detailed record of athletes' coaching and support personnel.

The IWF's anti-doping programme will be handed over to an Independent Testing Authority.

"Today marks the start of a new chapter for international weightlifting," said Ajan. "The Olympic Movement can trust that we are doing, and will continue to do, everything in our power to address the incidence of doping in our sport."

A Clean Sport Commission set up by the IWF, including two German scientists, an American lawyer, and the president of the German Weightlifting Federation among its seven members, made the recommendations adopted this weekend, and will monitor progress over the next four years.

In June the IOC asked for an IWF report by December on how the governing body plans to deal with doping. Unless it is deemed "satisfactory" at an IOC meeting in Lausanne on Dec 5-6, weightlifting will lose its Olympic status after Tokyo 2020.

Because of the bans, and North Korea's decision not to enter, 13 of 15 current world champions will not compete in Anaheim, leaving Tunisia, Mongolia and New Zealand, who have no pedigree in the sport at this level, to contend for medals.

The US hope to win their first men's world championships medals in 20 years. The host nation's best chance of success is in the 69kg category with teenager Clarence 'CJ' Cummings, who has won four world titles at youth and junior level.