Cases in the capital, Tokyo, made up half of the new infections confirmed Friday.
Tokyo governor Yuriko Koike urged residents Saturday to refrain from making unnecessary trips outside of Tokyo in order to limit the spread of the virus.
There was also one death confirmed Friday, the health ministry said. This brings the total number of cases nationally to 19,994 (19,282 on land and 712 on the Diamond Princess cruise ship) and the death toll to 990, of which 13 were on the cruise ship.