Japan expanded a coronavirus state of emergency Friday, just 10 weeks before the Olympics, as campaigners submitted a petition with more than 350,000 signatures calling for the Games to be scrapped.

With Tokyo and other areas already under emergency orders until the end of May, three more regions -- including northern Hokkaido, which will host the Olympic marathon -- now join them.

"Today, we decided to add Hokkaido, Okayama and Hiroshima to the area under the state of emergency from May 16 to 31," Prime Minister Yoshihide Suga said.

In these regions, "the population is relatively big and the number of new cases is very rapidly increasing", he said.

The widening emergency, aimed at combatting a fourth wave putting Japan's medical system under strain, comes with public opinion firmly opposed to holding the Games this summer, fearing further infections.

More than 351,000 people have signed a petition calling for the Tokyo Games to be cancelled
More than 351,000 people have signed a petition calling for the Tokyo Games to be cancelled AFP / Kazuhiro NOGI

Kenji Utsunomiya, a former candidate for Tokyo governor, urged Games organisers to "prioritise life" as he submitted the 351,000-signature petition to city authorities.

"I think the Olympics this time is about whether we prioritise life or a ceremony and event called the Olympics," Utsunomiya said, urging Tokyo Governor Yuriko Koike to push for cancellation.

The petition is also being sent to the International Olympic Committee and International Paralympic Committee, as well as local organisers and the national government.

"Holding the Olympics under these circumstances means precious medical resources have to be set aside for the Games," Utsunomiya warned.

Thursday saw a doctors' union warn it was "impossible" to hold the Games safely during the pandemic, but organisers say virus countermeasures will keep the athletes and Japanese public safe.

Polls consistently show a majority of Japanese oppose holding the Games this year, favouring either a further delay or cancellation due to the coronavirus pandemic
Polls consistently show a majority of Japanese oppose holding the Games this year, favouring either a further delay or cancellation due to the coronavirus pandemic AFP / Charly TRIBALLEAU

Tokyo 2020 chief Seiko Hashimoto told reporters she was aware of the concerns, but insisted "very stringent antivirus measures" would be in place.

"We have to create a firm bubble and take the necessary restrictions to avoid putting strain on the medical system," she told reporters.

Addressing fears about the tens of thousands of journalists and officials expected to enter Japan along with the Olympic athletes, Suga said rulebreakers could face tough punishments.

"There are restrictions on behaviour. For those who violate the rules, we're discussing measures including deportation," he said.

Several Olympic test events are taking place in Tokyo, including skateboarding
Several Olympic test events are taking place in Tokyo, including skateboarding AFP / Behrouz MEHRI

In an interview with AFP, International Paralympic Committee chief Andrew Parsons acknowledged Japanese "anger" over the Games.

But he said strict rules, including daily testing and limited movement for athletes, meant the chance they could infect anyone was "really remote".

"We want to provide this feeling of certainty," Parsons said.

"Because we see that the anger comes from this concept that it's the Japanese population's safety versus the Games. I believe they can coexist."

In recent days, organisers have held a string of successful test events, including with international athletes, which they say shows their protocols will work.

World Athletics chief Sebastian Coe, who attended test events in Japan last week, said no major sports event so far has been a "super-spreader".

"The world does need to keep moving," Coe wrote in the Daily Mail.

"At a time when football, rugby, tennis and athletics are all back functioning, and crowds slowly returning, it would seem odd to pull stumps on an Olympic Games where the protocols will be tougher than in any other walk of life and many competitors and their support teams will be arriving having been vaccinated."

In Japan, however, one of the country's most prominent businessmen, SoftBank CEO Masayoshi Son, said he is "afraid" of the Games going ahead.

"I am very much afraid of having the Olympics," he told CNBC.

"Not just Japan, but many countries they're having still a big, tough situation, I don't know how they can support sending athletes."

Several top Japanese sports stars, including tennis Grand Slam-winner Naomi Osaka and Masters golf champion Hideki Matsuyama, have expressed reservations about holding the Games during the pandemic.

Utsunomiya said his petition would continue to gather signatures "until the cancellation is announced", and brushed aside the cost of scrapping the massive event.

"People's lives are more important than money," he said.