Former Prime Minister Shinzo Abe has been questioned by prosecutors over allegations that his political group illegally covered part of the cost of dinner receptions for supporters, sources close to the matter said Tuesday.

The prosecutors, who questioned Abe on Monday, have already decided to build a case against Abe's state-paid secretary for allegedly not recording incomes and expenditures related to the dinner events. Total revenues and costs not declared in political fund reports may exceed ¥40 million, they said.

Abe is likely to have denied his involvement in not recording funds related to the dinner functions, the sources said, adding that prosecutors were therefore unlikely to proceed with building the case against the former prime minister.