BEIJING, July 21 (Xinhua) -- China reiterates its stance of zero-tolerance on doping ahead of the Rio Olympic Games.

Gao Zhidan, China's General Administration of Sport vice director, told Xinhua that the country has been firm in cracking down on doping.

"China have been firmly against doping and have a zero-tolerance approach to this particular problem," said Gao who is also deputy chef de mission of China's 711-member delegation to the Rio Games.

"We have adopted a series of measures to keep our athletes clean, such as the admission system which requires every Rio-bound athlete, coach and team doctor to pass a written test. Those who fail the test will not be able to go to Rio," said Gao. Eighty points out of 100 are needed to pass the test.

"Rio-bound athletes and coaches are also required to sign a pledge not to use banned drugs and rule violators will be punished severely," he said.

"We have made it very clear that we want to ensure fair play and the well-being of athletes," he said.