The health minister said Sunday it will be "very difficult" to lift a COVID-19 state of emergency on its planned Sept. 12 expiry, as the country is still struggling to contain surging coronavirus infections and strain on the medical system.

"Given the current situation, it's probably very difficult" to end the emergency declaration covering 21 prefectures as scheduled, health minister Norihisa Tamura said on an NHK TV program.

The number of daily COVID-19 cases in Tokyo, for example, must fall below 500 for the state of emergency to be lifted, he said. The capital reported 3,081 new COVID-19 cases Sunday, with no clear signs of the surge abating anytime soon.