The governor of Tokyo resigned Thursday after he admitted receiving an undeclared $500,000 from a hospital tycoon ahead of his election, in what he claimed was an interest-free, personal loan.
Naoki Inose, who was elected head of one of the world's biggest cities a year ago, had faced weeks of intense pressure over suspicions that the money amounted to a bung and an attempt to influence policy.
"I have decided to resign from the post of Tokyo governor," Inose told a hurriedly arranged press conference.
"I intended to fulfil my duty of explaining to the city assembly, people of Tokyo and people of the nation, but regrettably I could not clear doubts over me. It's solely because of my lack of virtue."
Inose, who lost his wife to cancer earlier this year, was a key figure in Tokyo's successful bid for the 2020 Olympics, and said his resignation was partially aimed at avoiding a negative impact on preparations for the Games.
Writer-turned-politician Inose admitted in November he had received 50 million yen ($500,000) from the political family behind the huge Tokushukai medical group before running in last year's gubernatorial election.
He did not declare the sum in his campaign accounts, but insisted that it was not any kind of slush fund.
Under Japanese election law, campaign treasurers must report all income, such as donations, related to electioneering. Those who violate the law can face prison terms of up to three years or fines of up to 500,000 yen.
Inose, who inherited the mantle of Tokyo governor from firebrand nationalist Shintaro Ishihara, has cut an increasingly lonely figure over the past few weeks as the furore around him swelled.
He has been grilled by a hostile assembly on several occasions, with the media picking apart his physical appearance and his stuttering performance, focusing on the beads of sweat that dripped down his neck.
At hearings and in press conferences he has waved around a piece of paper that he insisted amounted to a loan agreement, although observers noted that it bore no date for repayment and showed no terms and conditions.
On another occasion, he produced a bag in which he claimed to have carried the large bundle of cash. Opponents delighted in trying to prove that the sum would not fit inside the holdall.
"I was an amateur politician"
On Thursday, the 67-year-old Inose admitted he had been naive about the cut and thrust of Japan's politics.
"I didn't know how strict professional politicians need to be," he said, adding he was not clear about all the procedures he was supposed to follow.
"I was an amateur politician even though I knew well about policies. I myself thought it was extraordinary that I became Tokyo governor," he added.
Pressure grew when Prime Minister Shinzo Abe was reported to be keen on drawing a line under the scandal.
"The fact that (Inose) received a large sum of money from someone who does business related to his authority (to approve hospital openings) is enough to warrant his resignation," Masahiko Komura, deputy head of Abe's ruling Liberal Democratic Party, told reporters Wednesday, according to Kyodo.
"If he delays his decision, Tokyo's preparations for the 2020 Olympics will be affected," Komura said.
Inose said in November that he was offered the money by the Tokudas, the family running Tokushukai, and that he felt "it would be rude to refuse when (the money was) offered".
But public broadcaster NHK reported that it was Inose himself who reached out to the Tokuda family and asked for 100 million yen before the election.
Prosecutors have investigated the Tokushukai group, which runs dozens of major hospitals throughout the nation, over allegations of illegal electioneering practices, including providing money to campaign workers when a family member ran for the lower house of parliament.
Inose said he paid back the "loan" after the investigation surfaced in September.
He said he was only able to return the money after the probe because he had been busy running Tokyo's bid to host the 2020 Olympics, and attending to his dying wife.