Bach says Games not 'tainted' by doping

International Olympic Committee (IOC) president Thomas Bach says the fight against doping continues and suggested it could never be won, but confirmed that a ban on Russia would be lifted if further doping tests at the PyeongChang Games were negative.

"We cannot ignore human reality," Bach said on Sunday, hours before the closing ceremony of the Winter Games.

Bach said two doping cases involving Russian athletes at the Games "played the major role" in deciding that Russia remain banned and can't march under their own flag at the closing ceremony.

"If there are no positive results the sanction is considered to be lifted," he said, adding that this would be "automatic" if confirmed by the Doping Free Sports Unit (DFSU).

"I don't think these Olympic Games have been been tainted by the affair," he said.

"These are cases of negligence and there is no indication for a systemic doping affair here or any involvement of the Olympic Athletes from Russia leadership or the Russian Olympic Committee."

Curler Alexandr Krushelnitckii and bobsledder Nadezhda Sergeeva both tested positive during the Games.

The way the IOC had dealt with the wider Russian doping affair, allowing 168 Russians to compete as neutral OAR athletes, "is not a blueprint because I hope this affair remains a unique one," he said.

Bach said the Games had sent a "powerful message" with the thawing of relations between South Korea and the North.

"We hope now that the political world will use this momentum for the dialogue on their level because now it's up to the politicians," he said.