Tokyo confirmed 224 COVID-19 cases on Thursday, a record high for single day figures, topping 200 for the first time since April 17.
Thursday's total is the second time for daily figures to top 200. The previous high was 206.
Neighboring prefectures have also been recording more infections. On Wednesday, Saitama Prefecture reported 48 cases, the highest in nearly two months. Kanagawa Prefecture has also seen its weekly average of new infections exceed its monitoring criteria of 10 over the past several days. The prefecture confirmed 25 cases on Thursday.
Elsewhere, Osaka recorded 30 cases on Thursday, NHK reported.
The Tokyo government has said the recent spike is mainly due to more people getting tested, especially those working at nightlife entertainment facilities, such as host clubs and hostess bars.
During a panel meeting under the Tokyo government held on Thursday, experts also said the increase is partly the result of a more robust testing system.
The majority of recently infected individuals are in their 20s and 30s.
Tokyo currently has six coronavirus patients who are in a critical condition, while the city has recorded no confirmed deaths from the virus for two weeks.