Restrictions include the grand start in disaster-hit Fukushima on March 26 taking place without fans.

Spectators will still be able to watch from the roadside but have been asked not to do so if they are feeling unwell.

Torchbearers will not be allowed to run if they have a high temperature and arrival and departure ceremonies for the Flame will also take place without an audience present.

"It is heartbreaking for us," said Muto, who reiterated the official stance that the Olympics would go ahead as planned from July 24.

He admitted, however, that the coronavirus situation was changing "hour to hour".

Fukushima was picked as the start of the Relay as organisers want to promote the region's recovery after the 2011 earthquake and tsunami which killed around 16,000 people.

The grand start is scheduled for J-Village, a football stadium and training centre which was used as an operational base in response to the tragedy.

It only re-opened again in April after the natural disaster, which caused an nuclear power plant to melt down.

Japanese footballers who lifted the FIFA Women's World Cup in 2011 have been tipped to be the first runners on home soil.

Coronavirus has already caused the cancellation of the Greek leg of the Torch Relay, which began after the Tokyo 2020 Flame was lit at Ancient Olympia last Thursday (March 12).

The Flame will be officially handed from Greece to Tokyo on Thursday (March 19) but the ceremony at the Panathinaiko Stadium in Athens has also been scaled back and will not be open to the general public.