More than 80 percent of Japanese polled oppose hosting the virus-postponed Olympics this year, a new survey showed on Monday, underlining public antipathy less than 10 weeks before the Tokyo Games.

The latest downbeat poll comes after Japan expanded a coronavirus state of emergency Friday as the nation battles a fourth wave of infections.

The surge in cases has put pressure on the country's healthcare system, with medical professionals repeatedly warning about shortages and burnout.

The weekend poll by the Asahi Shimbun daily found 43 percent of respondents want the 2020 Games cancelled, with 40 percent wanting a further postponement.

Those figures are up from the 35 percent who backed cancellation in a survey by the paper a month ago and the 34 percent who wanted a further delay.

"I am one of those in the 80 percent. I think the Olympics should be postponed. Is it that difficult to postpone it?" passer-by Sumiko Usui, 74, told AFP in Tokyo.

Takahiro Yoshida, 53, also expressed doubts over the event.

Polls have consistently found a majority of Japanese oppose holding the Games this summer
Polls have consistently found a majority of Japanese oppose holding the Games this summer AFP / Kazuhiro NOGI

"In my honest opinion, it will be difficult to hold the Games... Athletes from overseas must be worried as well, because Japan's coronavirus situation is bad," he said.

Only 14 percent support holding the Games this summer as scheduled, down from 28 percent, according to the Asahi poll of 1,527 replies from 3,191 telephone calls.

If the Games go ahead, 59 percent of respondents said they want no spectators, with a third backing lower fan numbers and only three percent a regular-capacity Games.

For months, polling has found a majority in Japan oppose holding the Games this summer.

A separate poll by Kyodo News published Sunday showed 59.7 percent back cancellation, though further postponement was not listed as an option.

Olympic organisers say tough anti-virus measures, including regular testing of athletes and a ban on overseas fans, will keep the Games safe.

Seats were blocked off at a BMX test event for the Tokyo Olympics
Seats were blocked off at a BMX test event for the Tokyo Olympics AFP / CHARLY TRIBALLEAU

But the Kyodo poll found 87.7 percent of respondents worry that an influx of athletes and staff members from abroad may spread the virus.

Amid mounting public opposition to the games, several dozen protesters rallied in central Tokyo against the Olympics.

"It's obvious to everyone that we should cancel the Games, but nobody -- the Tokyo 2020 organising committee, the Tokyo government nor Prime Minister (Yoshihide) Suga -- none of them are making the decision," Toshio Miyazaki, 60, who organised the demonstration, told AFP.

"We cannot afford to host the Olympics when we have to defeat the coronavirus."

Another demonstrator slammed government policy as "contradictory".

"If authorities put priority on the economy, I want them to lift the restrictions on restaurants and bars," Yusuke Kawai, a 40-year-old match-making party organiser, said.

"If they prioritise the anti-virus measures, I want them to cancel the Olympics."

Asked about the state of public opinion Monday, government spokesman Katsunobu Kato said the administration would "make efforts so that the Japanese people understand the Tokyo Games will be held in a safe and secure manner".

"We need to give explanations on details of the concrete (coronavirus) measures," he said, insisting that the Games would not put further pressure on medical services.

Japan has seen a smaller Covid-19 outbreak than many countries, with fewer than 11,500 deaths so far. But the government has come under pressure for its vaccine rollout.

The Kyodo poll found 85 percent of respondents considered the rollout slow, with 71.5 percent unhappy with the government's handling of the pandemic.

Thousands of slots were snapped up on Monday as online bookings opened for two mass vaccination centres which will deliver up to 10,000 shots a day in Tokyo and 5,000 in Osaka, initially to the elderly.

All 25,000 available slots were already booked up in Osaka, the centre said, while around 21,000 reservations were made in Tokyo.