Last April, a female reporter from TV Asahi accused Junichi Fukuda, the top bureaucrat at the Finance Ministry, of sexual harassment.
The woman recorded the conversation, excerpts of which were later published by weekly magazine Shukan Shincho.
The magazine also released an edited audio clip said to be of Fukuda telling the woman: "Can I touch your breast?" "Should we have an affair when the budget is enacted?" and "I will tie your hands."