Tokyo:Tokyo is reporting 920 new coronavirus cases, the highest since mid-May, two weeks ahead of the Olympics.
Prime Minister Yoshihide Suga held a meeting with key ministers to discuss coronavirus measures.
Suga noted Tokyo's upsurge and vowed "to do everything we can to prevent the further spread of the infections."
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Suga says he'll make a final decision on reinstating the state of emergency on Thursday after consulting with a panel of experts.
A state of emergency in Tokyo just before the games on July 23 would mean Olympic officials abandon plans to have local spectators or lower capacities at venues.
Dr Shigeru Omi, a top government medical adviser, urged authorities to quickly take tough measures ahead of the Olympics and summer vacations when many people tend to be more active.
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"The period from July to September is the most critical time for Japan's COVID-19 measures," he says.
Only 15 per cent of the Japanese were fully vaccinated. Japan has reported about 810,000 cases and nearly 14,900 deaths.
PTI