Former ruling Liberal Democratic Party lawmaker Mito Kakizawa pleaded guilty on Wednesday to allegations of illegal campaign financing related to a Tokyo ward election last April.

"I have decided not to contest any of the charges," the 53-year-old former senior vice justice minister said at the first hearing of his trial at the Tokyo District Court, acknowledging that he bears "heavy" responsibility.

Mito Kakizawa. (Kyodo)

Kakizawa has been indicted for violating the election law by making payments, or having offered to do so, totaling about 2.8 million yen ($19,000) for bribery in connection with the Koto Ward mayoral election, in which former LDP lawmaker Yayoi Kimura -- a candidate he backed -- won.

Kakizawa was also involved in Kimura's use of a paid online advertisement in the campaign, another violation of the election law.

Prosecutors believe Kakizawa was in a position equivalent to a "manager" in the campaign, having been involved in its planning and other activities. The court is scheduled to hand down a sentence on March 14 under a speedy deliberation process.

Kakizawa was arrested in December, along with his secretaries. He was serving his fifth term as a House of Representatives member, but stepped down as a lawmaker earlier this month following his indictment.

Around February last year, Kakizawa is suspected of having conspired with some of his secretaries to provide a total of 1 million yen to five former or incumbent Koto assembly members while offering payments totaling 600,000 yen to three others, according to the indictment.

Other allegations included a payment of 400,000 yen to a staff member of Kimura between around March and April, and transferring around 800,000 yen between around July and October to a former local assembly member who is said to have campaigned for Kimura.

Kimura, 58, has been indicted without arrest over an alleged election law violation for using the paid advert on YouTube and a payment of 1 million yen to the former local assembly member.

She had resigned as mayor in November after accusations of her use of the advert surfaced.

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