Australian Prime Minister Malcolm Turnbull said on Monday he was confident his government's one-seat majority was safe, despite questions over his deputy's citizenship which could disqualify him from parliament.
Deputy Prime Minister Barnaby Joyce said earlier on Monday that he may not be eligible for parliament after being told he may be a dual citizen of Australia and New Zealand.
The New Zealand government later said Joyce held New Zealand citizenship by descent as his father was born in New Zealand.
Australian politicians are not eligible to be elected to parliament if they hold dual or plural citizenship, a rule that has forced the resignation of two senators in recent weeks.
Turnbull's one-seat majority would be eliminated if Joyce was forced from office, likely triggering an election, political analysts said.
Joyce said he has asked Australia's High Court to decide the matter.
"The government is very confident the court will not find that the member for New England is to be disqualified from the Parliament. Very confident," Turnbull told parliament.
Opposition Labor MP Tony Burke told parliament Joyce should stand aside from the ministry and the government should not accept his vote.
"We've never before in this parliament...had to go to the High Court and say: 'Look, we're not really sure if there's a majority government in this country'," he said.
Joyce said he would not resign or temporarily step down from office after being told by Australian Solicitor-General Stephen Donaghue that he would likely be cleared by the High Court.
"Neither I nor my parents have ever had any reason to believe that I may be a citizen of any other country," he said.
Joyce's mother was Australian and his father was born in New Zealand and came to Australia in 1947 as a British subject.
If Joyce was disqualified, Turnbull would be forced to rely on the support of independents to prevent a successful no-confidence vote from the opposition Labor Party.
"I think if Joyce is forced out, Turnbull would call an election," said Peter Chen, a senior lecturer in government at the University of Sydney.
Recent polls suggest Turnbull would lose an early election, with his government bleeding support to the populist far-right One Nation party, while moderates have flocked to Labor as Turnbull struggles to deliver on his progressive reputation. Last updated: August 14 2017 10:03 AM