Japan confirmed 554 daily coronavirus cases Sunday, a new high since the Omicron variant was first detected in late November, amid a steady increase of infections involving the highly transmissible strain in the midst of the country's New Year holidays.

The figure was up from 534 reported the previous day, with the cumulative total of Omicron infections rising to 695 as of 9 p.m. Saturday from 637 a day earlier, according to a Kyodo News tally and data from the Ministry of Health, Labor and Welfare.

New cases in the country have continued to increase since over 500 daily COVID-19 infections were reported for the first time in two months in late December. Daily infections had been declining since hitting a peak of over 25,000 in the summer, with more than 75 percent of the population inoculated with two vaccine shots.

Ibaraki, Kagawa and Kochi prefectures all reported their first Omicron cases the same day, in what were believed to be community transmissions. Chiba, Kanagawa, Aichi, Kyoto, Osaka and Shimane prefectures also confirmed additional cases of the new variant.

Prime Minister Fumio Kishida said in a New Year's address Saturday that he would continue to take necessary measures to fight the spread of COVID-19. The government has been aiming to speed up the rollout of coronavirus vaccine booster shots amid multiple community transmissions of the Omicron variant across the country.

Epidemiologists have suggested that the prime minister shift the government's focus in the fight against the Omicron variant to domestic measures, as border enforcement alone has not contained infections.

The number of patients with serious symptoms nationwide increased by two from the day before to 53, according to the health ministry.

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