Chinese swimmers taking part in the Olympic Games in Paris will be drug-tested twice as much as some other nations.

Doping authorities have come under pressure in recent months after it emerged 23 swimmers tested positive for a banned substance and were cleared to compete at the Tokyo Games.

Eleven of those swimmers – that tested positive for heart medication trimetazidine (TMZ) at a training camp seven months before the delayed Games in 2021 – have been chosen for Paris.

Governing body World Aquatics, in a review of the decision to clear the 23 swimmers, said trust in the anti-doping system had been “weakened” by the handling of the situation.

But it said the International Testing Agency (ITA) has committed to testing Chinese athletes eight times – twice as much as is standard – between the start of 2024 and the beginning of the Games in Paris.

In addition, “best efforts” will be made to have tests of Chinese athletes conducted by an authority other than the China Anti-Doping Agency (Chinada) and to have the tests analysed outside of China.

World Aquatics is seeking to reassure athletes after Michael Phelps, the most decorated Olympian of all-time, said the World Anti-Doping Agency (Wada) cannot be trusted to enforce its policies.

US anti-doping authorities have also been critical of Wada, which has threatened legal action against its critics.

The International Olympic Committee says it has “full confidence” in Wada and has called on sporting agencies to show “respect” to the anti-doping body.