Former State Minister of Defense Miyazawa Hiroyuki has resigned as a Diet lawmaker following a report of an alleged extra-marital affair.
Miyazawa's letter of resignation was approved unanimously at the Lower House plenary session on Thursday. He was absent from the meeting.
Miyazawa had handed in the letter to the chamber's speaker on Tuesday and left the main ruling Liberal Democratic Party on Wednesday.
He had cited personal circumstances as the reason for his resignation.
But the "Bunshun" online journal has reported that Miyazawa lived with a woman who is not his wife, and financially assisted her.
Miyazawa is 49 years old. He was elected to the Lower House four times, most recently from the Tokai bloc under the proportional representation system.
He belonged to the party's largest faction that was previously led by the late former Prime Minister Abe Shinzo.
Miyazawa took up the post of state minister of defense in September last year, but stepped down in December over the fundraising scandal involving the faction.
Mori Yukiko, who is on the LDP's list of candidates for the Tokai bloc, is expected to replace Miyazawa in the Lower House.