TOKYO, June 7 (Xinhua) -- The head of an IT firm admitted that he had created videos criticizing rivals of Japanese Prime Minister Sanae Takaichi in last year's ruling Liberal Democratic Party (LDP) presidential race, after being asked to help her win the election, Kyodo News reported Sunday.

Japanese Prime Minister Sanae Takaichi speaks at a press conference at the prime minister's official residence in Tokyo, Japan, Jan. 19, 2026. (Photo: Xinhua)

In a recent online interview with Kyodo News, Ken Matsui, 33, said that he was consulted by a secretary of Takaichi on how to "reverse" the lead of her main rival Shinjiro Koizumi in the October election and proposed that "negative videos would be effective."

Matsui was asked about his thoughts during an online meeting, which included the secretary who was introduced to him by an acquaintance, on Sept. 25 to discuss social media strategy during the LDP election campaign, the report said.

According to Matsui, the videos not only targeted Koizumi but also another leadership rival, then Chief Cabinet Secretary Yoshimasa Hayashi who was emerging as another leading contender.

Matsui said he used some original generative artificial intelligence software to create 1,000 to 1,500 short videos on Koizumi and Hayashi, while around 300 social media accounts were then created on which the videos were shared.

Matsui said he does not think his actions violated the law.

Takaichi won the LDP presidential election on Oct. 4, 2025 and became the country's first female prime minister later that month.

Speaking in parliament in May, Takaichi denied reports saying her team spread malicious smear videos targeting political rivals.

In a written response to Kyodo News, Takaichi's office denied such allegations and said it has no plans to re-investigate the claims.

The reports, which first appeared in Shukan Bunshun in late April, claimed that Takaichi's publicly funded first secretary and others made and posted videos criticizing politicians including Koizumi. The weekly magazine said it had obtained substantial evidence supporting the allegations.