Japan has placed Tokyo under a state of emergency that will last throughout the Olympics amid fears that an ongoing COVID-19 surge will multiply during the Games.
Prime Minister Yoshihide Suga said the state of emergency would go into effect on Monday and last through until 22 August.
This means the Olympics, opening on 23 July and running through until 8 August, will be held entirely under emergency measures.
Mr Suga said the state of emergency was needed to "prevent the resurgence of the future spread of cases across the country".
The announcement came as International Olympic Committee (IOC) president Thomas Bach arrived in the city two weeks before the postponed Games are to open.
Mr Bach largely avoided cameras at Tokyo's Haneda Airport and went to the International Olympic Committee's Games headquarters in Tokyo, a five-star hotel in the centre of the city.
The main focus of the emergency is a request for bars, restaurants and karaoke parlours serving alcohol to close.
A ban on serving alcohol is a key step to tone down Olympic-related festivities and keep people from drinking and partying.
Japanese Prime Minister Yoshihide Suga attends a press conference at his office in Tokyo. Source: Kydpl Kyodo
Tokyo residents are expected to face stay-home requests and to watch the Games on television from home.
"How to stop people enjoying the Olympics from going out for drinks is a main issue," Health Minister Norihisa Tamura said.
The present state of emergency ends on Sunday.
Tokyo reported 920 new cases on Wednesday, up from 714 a week earlier.
It was the 18th straight day of week-on-week increases, and was the highest total since 1,010 were reported on May 13.
Fans from abroad were banned months ago from attending the Olympics.
But just two weeks ago, organisers and the IOC decided to allow venues to be filled to 50 per cent of capacity but crowds not to exceed 10,000.
The state of emergency will force them to change plans again, with a decision probably coming later on Thursday.
The soaring cases are likely to mean that venues will be without any spectators, although sponsors and others may have access.
The no-fan atmosphere could include the opening ceremony at the National Stadium.
The increase in infections has also forced the Tokyo city government to pull the Olympic torch relay off capital streets, allowing it to run only on remote islands off the Tokyo coast.
It is unclear how the torch will enter the stadium for the opening ceremony.
"The infections are in their expansion phase and everyone in this country must firmly understand the seriousness of it," Dr Shigeru Omi, a top government medical adviser, said.
He urged authorities to quickly take tough measures ahead of the Olympics, with summer holidays approaching.
Dr Omi has repeatedly called for a ban on spectators, and has said it is "abnormal" to hold the Olympics during a pandemic.
The Olympics are pushing ahead against most medical advice, partially because the postponement stalled the IOC's income flow.
About 11,000 Olympians and 4,400 Paralympians are expected to enter Japan, with tens of thousands of officials, judges, administrators, sponsors, broadcasters and media also entering.
The IOC says more than 80 per cent of residents of the Olympic Village will be vaccinated.
Nationwide, Japan has had about 810,000 cases and nearly 14,900 deaths.
Only 15 per cent of Japanese are fully vaccinated, still low compared with 47.4 per cent in the United States and almost 50 per cent in Britain.
