New farm minister Hiroshi Moriyama vowed Wednesday to pay back donations from companies involved in bid-rigging that were made to the ruling Liberal Democratic Party chapter he heads in Kagoshima Prefecture.

Moriyama, who assumed his post last week, confirmed a media report that the chapter received ¥6.9 million ($57,660) over three years from some of the 31 companies that the prefectural government barred in November 2010 from bidding for public works contracts due to bid-rigging alleged by the Japan Fair Trade Commission.

"As a politician, I have to deal with the issue ethically, although there was no legal problem," Moriyama told reporters in explaining his decision to return the money, while denying any intention to resign as agriculture, forestry and fisheries minister.

The LDP chapter's political funds reports show that it received ¥2.8 million from nine of the 31 companies in 2011, ¥1.68 million from six in 2012 and ¥2.5 million from nine in 2013.

During the period when the donations were made, the 31 companies sought mediation by a local summary court over the prefectural government's imposition of ¥3.6 billion in fines in 2013 and obtained its agreement to halve the penalties in 2014.

The LDP branch was found in 2010 to have received ¥5.5 million from 11 of the 31 companies during the 2007 to 2008 period when they rigged bids as alleged by the antimonopoly watchdog.