Japan extended a virus state of emergency in the Tokyo area by two weeks on Friday, less than five months before the pandemic-postponed Tokyo Olympics.
Prime Minister Yoshihide Suga announced the decision, which affects the capital and three nearby regions, and warned people against holding traditional spring picnics under cherry blossom trees.
"I ask you all to refrain from eating in large groups -- even at graduation ceremonies, enrollment ceremonies, welcome or farewell parties and flower-viewing parties," he said.
Despite a spike in infections this winter, Japan has seen a comparatively small outbreak overall with around 8,100 deaths, and has avoided imposing the blanket lockdowns seen in other countries.
The state of emergency, which primarily calls for bars and restaurants to close from 8pm, had been due to end on Sunday and was lifted early in other regions.
It has brought infections down in the capital but the rate of decline is slowing and experts warn of a potential resurgence when restrictions are removed.
It will now continue in Tokyo, Saitama, Chiba and Kanagawa prefectures until March 21 -- four days before the nationwide Olympic torch relay kicks off in northeastern Fukushima prefecture.
The two-week extension could cost the economy an extra 700 billion yen ($6.5 billion) in lost consumption, Tokyo-based think-tank NRI predicted.
Tokyo logged around 270 daily cases on average over the past week.
Japan's response to the virus is in the spotlight as Tokyo prepares to host the postponed Olympics, due to start on July 23.
Tokyo 2020 organisers have outlined measures they say will keep the Games safe -- even without requiring participants to be vaccinated or quarantined on arrival.
Border restrictions currently bar almost all foreign arrivals, which has forced the postponement of the year's first Olympic test event, an artistic swimming qualifier.
Japan began its vaccination programme in a limited fashion on February 17 and has so far given first doses to around 39,000 healthcare workers.
On Monday, Moderna filed for approval of its Covid-19 vaccine in Japan, becoming the third drug firm to do so.
The Pfizer/BioNTech vaccine is so far the only jab approved for use in Japan. The AstraZeneca/Oxford vaccine was also filed for approval a month ago and domestic clinical trials are underway.