Former Japanese prime minister Shinzo Abe acknowledged Tuesday his office is being investigated for questionable expenses linked to a dinner party his office hosted for his supporters ahead of an annual cherry blossom viewing party — a scandal that has been on the backburner for months.

Abe made the comment in response to reports on Monday that the Tokyo District Public Prosecutors' Office has been interviewing his aides over the scandal. No one has been arrested so far. Abe, who was in power for nearly eight years as Japan's longest-serving leader, stepped down in mid-September, citing ill health, but some critics have said the scandal might have been a reason.