Japan's government approved tighter coronavirus measures for the capital and other areas on Friday, weeks after lifting a state of emergency and with just over 100 days until the postponed Tokyo Olympics.
The new restrictions are far less severe than the blanket lockdowns seen in other countries and mainly call for restaurants and bars to close at 8 pm, with the threat of fines for those that do not.
They are already in force in virus hotspots including Osaka city, where a rebound in cases has forced the Olympic torch relay off public roads.
The pandemic-delayed 2020 Games are due to open on July 23 in Tokyo, but a surge in cases in parts of the country is creating new concern.
"Today, we decided to take intensive measures to prevent an epidemic in Tokyo, Kyoto and Okinawa," Prime Minister Yoshihide Suga told a meeting of ministers and government officials.
"We made the decision based on the fact that the number of new infections is increasing and there is concern that the medical system could come under pressure in these regions," he added.
Kyoto city and areas of Okinawa covered by the new measures are usually flooded with visitors during the Golden Week holiday period from late April to early May. The new restrictions will last until May 5 in the two regions.
Japan's government imposed a virus state of emergency across several regions starting in January, lifting it gradually, with Tokyo exiting the measure last.
But cases have rebounded quickly in some areas where the measure was lifted sooner, particularly in Osaka.
Japan has avoided the severe Covid-19 outbreaks seen elsewhere and has suffered around 9,300 deaths overall.
But its vaccine rollout is moving slowly, with only the Pfizer/BioNTech jab approved so far, and physicians have reported the spread of more contagious variants.
Vaccinations for the elderly are planned to start next week with approvals for the Moderna and AstraZeneca/Oxford shots not expected before May.
The new measures will be in place from Monday until May 11 in the capital and could affect the torch relay further.
Tokyo 2020 organisers said in a statement that the relay route would be "subject to change" in areas where additional virus measures were in place.
"Tokyo 2020 will work closely with the Prefecture Task Force in each location in order to ensure the Olympic Torch Relay is carried out in utmost safety," it said.
Olympic organisers are pressing ahead with preparation for the Games, with national swimming qualifiers under way this week.
But some test events and qualifiers involving international officials and participants have been postponed because of Japan's strict anti-virus border controls.
Tokyo Governor Yuriko Koike made reference to the need to bring infections under control before the Games in discussing the new measures on Friday.
"In order to prevent the wide spread of the virus during the 2020 Games, and to ensure that everyone can move freely while taking precautions, I believe that we need to take steps to make efforts to reduce cases when we are seeing a sharp rise," Koike told reporters on Friday.