The International Olympic Committee is facing its strongest headwinds in decades as it prepares to brief national committees on Wednesday, as Japan insisted it is not planning for a postponed games.

The IOC has remained committed to staging the Tokyo Games planned from 24 July to 9 August, saying on Tuesday after a meeting with international sports federations that measures against the virus were delivering results.

The coronavirus has so far killed more than 7,500 people and infected about 200,000, with the epicentre now in Europe.

The IOC has refused to publicly consider cancellation or postponement as possible options, even as other major events including soccer's Euro 2020 and Copa America and the French Open tennis grand slam announced postponements on Tuesday.

Japan is not making any preparations to postpone the 2020 Summer Olympics, the government's top spokesman said on Wednesday, stressing Tokyo's resolve to host the event as scheduled despite the global spread of coronavirus.

Chief Cabinet Secretary Yoshihide Suga said the government would continue with preparations as scheduled, working closely with organisations such as the International Olympic Committee (IOC).

"We're not making any adjustments to postpone the Games," Suga told parliament when asked by a lawmaker whether the government was making plans to cancel or postpone the event.

The virus has wreaked havoc with Olympic qualification tournaments with athletes struggling to train, travel or compete and many pre-Games qualifiers cancelled or postponed.

Sonia O'Sullivan has called for a postponement with others now airing their views on the situation.

IOC member Hayley Wickenheiser said the decision to proceed with the Games was "insensitive and irresponsible" in the most vocal attack on the Olympic body since President Thomas Bach took over in 2013.

Wickenheiser, who competed in five Winter Games in ice hockey and at the 2000 Summer Olympics in softball, said continuing with the Games as planned ignored the challenges posed by the coronavirus pandemic.

"This crisis is bigger than even the Olympics," Wickenheiser said in a statement on Twitter. "Athletes can't train. Attendees can't travel plan. Sponsors and marketers can't market with a degree of sensitivity."

"I think the IOC insisting this will move ahead, with such conviction, is insensitive and irresponsible given the state of humanity."

She is not alone.

Several athletes, including reigning Olympic pole vault champion Katerina Stefanidi, said the IOC decision was putting athletes' health at risk, urging them to train as normal when entire countries have shut down to contain the virus spread.

"There is no postponement, no cancellation. But it (the IOC) is putting us at risk," Stefanidi said in an exclusive interview to Reuters.

"We all want Tokyo to happen but what is the Plan B if it does not happen?

"Knowing about a possible option has a major effect on my training because I may be taking risks now that I would not take if I knew there was also the possibility of a Plan B."