The number of coronavirus patients with severe symptoms across Japan totaled 1,563 as of Saturday, up 42 from the previous day and hitting a record high for the third straight day, the health ministry said Sunday.

In Tokyo, daily COVID-19 cases totaled 4,295 on Sunday, the metropolitan government said, as it continues to struggle with a strain on the medical system in the capital due to a resurgence of the virus.

The seven-day rolling average of infections in Tokyo has risen to 4,263.9 per day, up 5.6 percent from the previous week.

Across Japan, daily coronavirus infections totaled around 17,900, according to local authorities. The nationwide tally had reached record levels above 20,000 for two straight days through Saturday.

Pressure has been growing on the central government to expand the state of emergency that currently covers Tokyo, Osaka and some other prefectures.

The alarming rise in infections has come amid the spread of the highly contagious Delta variant of the virus. Designated hospital beds in many prefectures are fully occupied.

Infectious disease experts have called for foot traffic in Tokyo to be cut by half from the level in early July, prior to the imposition of the current state of emergency in the capital, through measures such as limiting the number of visitors to underground food sections in department stores and shopping malls.