Japan announced a new coronavirus emergency in Tokyo and three other regions on Friday, as the country battles surging infections just three months before the Olympic opening ceremony.
The nation's virus outbreak remains much smaller than in many countries, but a recent uptick in cases has officials and medical professionals worried, even as the government and Olympic organisers insist this summer's Games will go ahead.
"Today we decided to declare a state of emergency in Tokyo, Kyoto, Osaka and Hyogo prefectures," Prime Minister Yoshihide Suga announced, citing the rise of infections involving new virus variants. The measure will run from April 25 to May 11.
The country's minister for virus response Yasutoshi Nishimura earlier warned of a "strong sense of crisis," saying current restrictions were not sufficient.
The measures will be tougher than Japan's last state of emergency, imposed in parts of the country from January, but still far short of the harsh lockdowns seen in some parts of the world.
Authorities want bars and restaurants to close, and to shutter major commercial facilities like malls.
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The measure will coincide with the Golden Week holiday that is Japan's busiest travel period of the year, and could involve cutting some train and bus services to discourage movement.
Spectators will also be barred from sports events, which can continue behind closed doors, and remote working will be encouraged.
Although the measures start from Sunday, Tokyo governor Yuriko Koike urged residents to start taking precautions immediately.
The spike in infections is already disrupting everything from the Olympic torch relay, which has been forced off public roads in several regions, to test events and qualifiers.
Australia withdrew from the Diving World Cup scheduled for May 1-6 in Tokyo, saying it was "not safe" to travel to Japan.
Japan's vaccine programme is moving slowly meanwhile, with just over 1.5 million people given a first shot and only around 827,000 fully vaccinated.