The death toll in mainland China from the coronavirus strain known as Covid-19 has risen by 97 to 2,442, Chinese health authorities have said.

This marked a slight fall on the number of new deaths in the 24 hours to Sunday morning, compared to the previous day.

Officials also announced 648 new infections, representing a spike compared to the downward trend of recent days.

The number of daily new cases also surged in South Korea, while the death toll in Iran climbed to six, the largest outside China.

Italian authorities said the number of people infected with the virus has more than quadrupled due to an emerging cluster of cases in the country’s north.

The deaths of two people from Covid-19 forced the postponement of three Serie A matches, with many of the new cases represented the first infections in Italy acquired through secondary contagion.

The total number of cases in China is 76,510, most of which are in Hubei, the province where Covid-19 originated.

Prior to the spike in daily infections, China’s leadership sounded a cautious note about the country’s progress in halting the spread of the virus, after several days of upbeat messages.

The Politburo, made up of the senior officials of the ruling Communist Party, said the situation in Hubei and its capital Wuhan remains grave.

“We should clearly see that the turning point of the development of the epidemic across the country hasn’t arrived yet,” the Politburo said at a meeting led by President Xi Jinping and reported by state broadcaster CCTV.