The International Olympic Committee (IOC) has told athletes to prepare for the Tokyo Olympics despite fears the threat of coronavirus could delay or even cancel the summer Games.

Key points: IOC president Thomas Bach urged athletes to go "full steam" with their preparations for the Games

IOC president Thomas Bach urged athletes to go "full steam" with their preparations for the Games The head of WHO said "deciding now could be too early" and it was best to monitor the situation

The head of WHO said "deciding now could be too early" and it was best to monitor the situation Japan's Olympics Minister said the Games could be postponed to later in the year

IOC president Thomas Bach gave his unequivocal backing to the Games going ahead as the committee's executive board met in Switzerland to discuss the event, set to run from July 24 to August 9.

"We are preparing for a successful Olympic Games, Tokyo 2020," Bach said in Lausanne.

"I would like to encourage all the athletes to continue their preparation for the Olympic Games, Tokyo 2020 with great confidence and full steam.

"From our side, we will continue to support the athletes and the national Olympic committees."

IOC spokesman Mark Adams said in no uncertain terms: "We are going to have the Games on July 24."

There have been nearly 1,000 coronavirus cases and 12 deaths in Japan, and the head of the World Health Organisation said, while he was confident coronavirus "can be contained", it was difficult to forecast too far ahead.

The outbreak risks disrupting the Tokyo Games along with other events in Japan. ( Reuters: Athit Perawongmetha )

"I have confidence in Japan and there will be hopefully progress. And at the same time, we are in discussion with the IOC," Tedros Adhanom Ghebreyesus told a Geneva news conference.

"We had a phone call with the president of the IOC and what we have agreed is, that we monitor the situation, and then if there is a need for any actions then we can discuss with the Japanese Government.

"But I think deciding now could be too early."

Canada's Dick Pound, the longest-serving member of the IOC, said last week that a call would be made by May.

Australian chef de mission Ian Chesterman wrote a letter to more than 1,000 athletes to keep them up to date with the latest plan, with the Australian Olympic Committee (AOC) preparing for a July 24 opening ceremony.

"I'm very heartened by discussions with athletes over the past few days; they are focused on their preparations and training," AOC chief Matt Carroll told RN Breakfast.

"We're still travelling to qualifiers around the world [and] all the international federations, the IOC and sports have been very cooperative in moving things around.

"At the end of the day the choice of going to the Games rests with the athletes. They will be able to make that decision.

"Just for the two weeks this has been four years of preparation."

Could the Games be delayed?

The Olympics have been cancelled only three times, all during wartime.

On Tuesday Japan's Olympics Minister Seiko Hashimoto said the host city contract "could be interpreted as allowing a postponement" before the end of the year.

"The IOC has the right to cancel the games only if they are not held during 2020," she said.

But Ms Hashimoto said the Government and the city of Tokyo were both committed to the Games starting on time.

The 1964 Tokyo Olympics were held in October, but the Games have since shifted to summer, in large part because it is one of the only time slots open for sports broadcasters around the world.

From October onwards, NFL, college football, baseball, basketball and hockey are all being played in North America, where NBC contributes about half of the $US5.7 billion ($8.7 billion) the Olympics gets from broadcast rights.

Meanwhile, Europe is jammed with football in England, Spain, Germany, France and Italy, not to mention cricket and rugby.

Japan has already asked all of its schools to close until April due to the outbreak and several major sporting events, including professional baseball games and the spring Sumo tournament, will take place behind closed doors due to the spread of coronavirus.

ABC/Reuters