The International Olympic Committee is considering a postponement of Tokyo 2020, and has given itself a deadline of four weeks to make a decision.
The IOC's executive board met on Sunday amid mounting pressure from athletes and national Olympic committees for the Games to be delayed because of the coronavirus crisis.
"In light of the worldwide deteriorating situation… the executive board has today initiated the next step in the IOC's scenario-planning," it said in a statement.
"These scenarios relate to modifying existing operational plans for the Games to go ahead on 24 July 2020, and also for changes to the start date of the Games."
Cancellation is "not on the agenda", said the IOC, but a "scaled-down" Games will also be considered.
However, postponement – by either several months or probably a whole year – is thought to be the most likely outcome.
The development marks a significant shift by the IOC, which as recently as five days ago said it was "fully committed" to the Tokyo 2020 Games.
British Olympic Association (BOA) chairman Sir Hugh Robertson said: "We welcome the IOC executive board decision to review the options in respect of a postponement of the Tokyo 2020 Olympic Games.
"However, we urge rapid decision-making for the sake of athletes who still face significant uncertainty.
"Restrictions now in place have removed the ability of athletes to compete on a level playing field and it simply does not seem appropriate to continue on the present course towards the Olympic Games in the current environment."
The International Paralympic Committee said it "fully supports" the decision to "investigate potential scenarios".
Dame Katherine Grainger, chair of UK Sport, said the news was "inevitable" and it was "the correct decision for the safety of athletes, staff and fans".
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On Tuesday the BOA, the British Paralympic Association and UK Sport will host a conference call with the chief executives and performance directors of summer Olympic and Paralympic sports.
Athlete representative bodies will also be invited to join the call, which will primarily be used to discuss the impact of the coronavirus pandemic in the UK, such as the closure of elite training facilities.
The IOC added: "There is a dramatic increase in cases and new outbreaks of Covid-19 in different countries on different continents. This led the executive board to the conclusion that the IOC needs to take the next step in its scenario-planning.
"The IOC will, in full coordination and partnership with the Tokyo 2020 Organising Committee, the Japanese authoritiesRead More – Source