Kishida, who took office in October 2021, has seen his popularity as well as his standing within the ruling Liberal Democratic Party sag ahead of a party leadership election next year.

The changes, expected to be announced on Wednesday, also come at a time when the key US ally is facing heightened tensions with China and North Korea.

Public broadcaster NHK and other media reported on Tuesday that Foreign Minister Yoshimasa Hayashi will be replaced by former justice minister Yoko Kamikawa, 70.

Kamikawa would be one of five women in the new lineup, NHK said, up from the current two members.

The number would be the joint highest along with the cabinets of 2001 and 2014.

Kamikawa was justice minister when Japan executed five years ago the leader and members of Aum Shinrikyo, sentenced to death for their role in the fatal 1995 sarin attack on the Tokyo subway.

Hayashi, who has been foreign minister since November 2021, made a surprise visit to Ukraine only this weekend.

The reports added Defence Minister Yasukazu Hamada will be succeeded by Minoru Kihara, 54, who served as parliamentary secretary of defence before.

Shunichi Suzuki was expected to retain his position as finance minister in the world's third-largest economy, the reports said.