Tokyo Metropolitan Government sources say over 1,300 new cases of coronavirus were confirmed in the Japanese capital on Thursday.
That marks the first time the daily tally has risen above 1,000. The previous high was 949, hit on Saturday.
Infections have been rising rapidly in Tokyo, with recent daily rates often exceeding 800.
Tokyo Governor Koike Yuriko warned on Wednesday that citizens face an unprecedented third wave of infections. She said cases could surge at any time, and urged people to avoid holding parties at home with friends or getting together with groups of relatives.
Koike said infections must be contained over the year-end holidays, and saving lives must be the priority. She warned of a possible state of emergency if the situation worsens.