Environment Minister Yuriko Koike was hospitalized Wednesday for treatment of acute pneumonia, Chief Cabinet Secretary Shinzo Abe said Thursday.
Koike, 53, has been told to rest for about a week, officials at her office said. She had a cold for about a week but had continued working until Wednesday.
Abe said it will take a few days to know when she will be able to return to work.
Koike was admitted to a Tokyo hospital Wednesday night with a high fever, Abe said. He said she is conscious and her condition is stable. She was taken to the hospital by ambulance, Environment Ministry officials said.