Tokyo Governor Yuriko Koike said on Thursday she would request the central government impose emergency measures to stem a surge of Covid-19 infections in the capital region.
Koike made the comments after a meeting with medical experts who warned of an explosive surge in cases that could exceed the third and most deadly wave of the pandemic so far. Experts also warned of a rise in more infectious mutant strains of the virus.
The western prefectures of Osaka, Hyogo and Miyagi started on Monday a month of targeted lockdown measures, to rein in a more virulent strain of the virus.
Tokyo's cases are on an uptrend as well, with Wednesday's 555 new infections standing at the highest since early February.
Prime Minister Yoshihide Suga said on Sunday that the measures, which allow regional governments to order restaurants to close early and levy fines for noncompliance, would be expanded as necessary.