Prosecutors are unlikely to charge Yoshimi Watanabe, the former head of the now-defunct opposition Your Party, over an alleged violation of the political funds control law, sources close to the matter said.

Watanabe, a 62-year-old political veteran who lost his Diet seat in the Dec. 14 general election, borrowed ¥90 million in 2010 from a bank account linked to his political funds group but repaid it. He also borrowed ¥80 million in 2013 from the same account.

Neither transaction was recorded in the group's funding report, raising questions over whether they violated the political funds control law.

The Tokyo District Public Prosecutor's Office's special investigative arm has questioned Watanabe on a voluntary basis to decide whether to pursue criminal charges against those who compiled the funding report.

The prosecutors are apparently unable to establish whether Watanabe or his accounting officer understood that the money should have been entered in the report, the sources said Wednesday.

When he quit as Your Party leader in April, Watanabe was under fire for receiving unreported loans totaling ¥800 million from the chairman of cosmetics firm DHC Corp.

The sources said it is unlikely prosecutors will lodge a case against Watanabe over those loans.