Opposition politicians are also increasingly frustrated with Suga, demanding he provide detailed answers to questions about the COVID-19 crisis and the Tokyo Olympics, which is set to start in less than six months.

Suga is struggling to halt a steady decline in support for his four-month-old government even after launching a raft of measures to contain a third wave of coronavirus infections.

Support for Suga's cabinet dropped to 33 per cent from 39 per cent last month, with disapproval rising 10 points to 45 per cent, according to a poll published by the Asahi newspaper on Monday.

The poll conducted by telephone on the weekend showed 80 per cent of respondents thought the government was too slow to declare a state of emergency in response to the coronavirus outbreak which has swept the country since December.

Infection data released over the weekend indicated that Japan's third, and most deadly, wave of COVID-19 infections was peaking.

Tokyo recorded 986 new cases on Sunday, falling below 1000 for the first time since January 12.

Nationwide the count was 3990, taking it below 4000 for the first time since January 4, public broadcaster NHK said.

Japan has had a total of 365,723 cases and 5120 deaths, NHK reported.

The Asahi poll came after opposition lawmakers criticised the brevity of Suga's answers to questions on the government's response to the COVID-19 crisis and the Olympics during a parliamentary debate on Thursday.

An Upper House steering committee petitioned Suga's office to provide more thorough responses during future debates, according to the Mainichi and Asahi newspapers.

"To get over it with an abstract, really short answer is the same as rejecting to explain it to the people," Mainichi quoted opposition Constitutional Democratic Party of Japan politician Tetsuro Fukuyama as saying last week.

Opinion polls show the public is strongly against holding the Olympics amid the pandemic.

Australian Associated Press