Peter Dutton insists he has never made money from a family trust linked to childcare centres owned by his wife, which opponents say put his eligibility to sit in parliament under a cloud.
The home affairs minister has faced ongoing questions about whether a financial interest in two publicly-funded Brisbane childcare centres could be in breach of the constitution.
Mr Dutton has remained confident about his eligibility, citing legal advice from Guy Reynolds SC and former solicitor-general David Bennett QC affirming his position.
"My wife's business is her business, I have never taken a dollar of dividend or distribution," he told the National Press Club in Canberra on Wednesday.
"I was very clear at the start that I would not take a dollar of distribution from that trust which she operates and I've been true to that."
He said the allegations had re-emerged during the week of his failed leadership challenge in August, indicating they were politically motivated.
"People can draw on their conclusions as to what the motivations were for raising it in the context of the leadership issue," Mr Dutton said.
"I think that's a very important point to highlight."
Labor has been trying to get Liberal MPs to cross the floor so it can refer Mr Dutton to the High Court to test his eligibility.
Former prime minister Malcolm Turnbull, who Mr Dutton tried to overthrow before Scott Morrison narrowly won the Liberal leadership, is among those who have called for him to be referred.
The constitution bans from parliament anyone who receives a direct or indirect pecuniary benefit from the Commonwealth.