A state of emergency was on Monday imposed in Japan's Chiba, Kanagawa, Saitama and Osaka prefectures, joining Tokyo and Okinawa, due to a resurgence in new Covid-19 cases.
The state of emergency for the four new prefectures will last until August 31, reports Xinhua news agency.
Meanwhile, the emergency period in Tokyo and Okinawa was also extended to August 31 from the originally planned August 22.
The Japanese government is planning to roll out standards for easing restrictions with the progress of vaccination of the population.
Under the state of emergency, establishments serving alcohol or offering karaoke services are asked to suspend their business, and those not serving liquor are requested to close at 8 p.m.
The government would offer monetary compensation for compliance.
Outside of the six prefectures, a quasi-state of emergency has been implemented in parts of Hokkaido, Ishikawa, Kyoto, Hyogo, and Fukuoka until the end of August.
The quasi-state of emergency is less restrictive on business activity than the state of emergency.
According to the government's policy, serving alcohol is prohibited and restaurants not serving liquor are asked to close at 8 p.m. under the quasi-state of emergency as well, and the local governors of the five prefectures could ease restrictions based on improvements in the situation.