Chief Cabinet Secretary Hirokazu Matsuno, the government's top spokesman, has tested positive for COVID-19, the latest high-profile politician to come down with the virus.
Matsuno, 59, is currently recovering at his home, the government said, adding that Prime Minister Fumio Kishida and other officials at the Prime Minister's Office were not in close contact with the chief Cabinet secretary.
Earlier this month, ruling Liberal Democratic Party lawmaker Taro Kono tested positive for the virus.
News of Matsuno's infection comes as Japan is battling a seventh wave of the virus, with the country reporting a record daily caseload for the fourth straight day on Saturday.