Tokyo, Osaka and two other prefectures are set to enter a state of emergency just three months before Japan's capital is due to host the rescheduled Olympic Games.

Restrictions will be imposed from April 25 through to May 11 in a bid to curb rising coronavirus infections in Japan.

Bars, restaurants and karaoke parlours serving alcohol will be asked to close, while sporting events are set to be held behind closed doors.

Additionally, department stores and cinemas will close, while people will be encouraged to work from home. Schools, however, will remain open.

Economy minister Yasutoshi Nishimura said: "We absolutely have to limit the movement of people, and we have to do it decisively.

"We need powerful, short and focused measures."

Kyoto and Hyogo are the other two areas to come under the new restrictions.

It marks the third time Japan will enter a state of emergency. The decision comes as the country's medical system struggles to contend with a rise in COVID-19 infections caused by new variants.

The Japanese government and the International Olympic Committee has not swayed from its stance that the Games – postponed last year as a result of the pandemic – will go ahead despite a strong swell of public support for a cancellation.

Last week, Toshihiro Nikai – the secretary general of Japan's ruling Liberal Democratic Party – said cancellation remains a possibility, although Olympics Minister Tamayo Maruyama said that was not being considered.

International spectators have already been banned from attending the Games, which are due to begin on July 23, while a decision over domestic spectators going to events is reportedly set to be delayed.