BARNABY Joyce is taking "urgent steps" to completely renounce his surprise New Zealand citizenship, the government has said.
It emerged on Monday that the deputy prime minister and Nationals leader is a dual citizen, seemingly putting him in breach of Section 44 of the Constitution and plunging Malcolm Turnbull's one-seat majority into jeopardy.
On Monday morning, Mr Joyce revealed to parliament that he learnt last week he could be a citizen of New Zealand by descent via his father.
Just hours later, New Zealand's Internal Affairs Minister Peter Dunne confirmed Mr Joyce was a New Zealand citizen under the Citizenship Act of 1948. Mr Dunne told local reporters that Crown Law had checked the circumstances and confirmed Mr Joyce was a citizen.
The country's prime minister Bill English also confirmed the problematic status, saying: "Unwittingly or not, he's a New Zealand citizen."
Mr Joyce's former rival for his seat of New England independent MP Tony Windsor told the ABC he could run for his old if a by-election was called.
"I'm in Alice Springs, just come out of the desert today, getting some vehicles fixed and a few other things. That's the main focus at the moment. But I'll be watching this," Mr Windsor told ABC TV.
"The issues that I stood on last time against Mr Joyce have gone from bad to worse.
"The National Broadband Network, for instance - I think country people in particular, but city people as well - have woken up to this massive con that's been perpetrated upon them.""Mr Joyce is the master of the minute - not master of the long-term.
"The law is the law. I don't particularly like that law. If they want to change it, they should have a good look at it.
"Why is Barnaby Joyce different to anybody else that has stood aside during this particular issue?"
WHAT COULD HAPPEN?
If Mr Joyce is found by the High Court to be ineligible to sit in Parliament, he will likely renounce his New Zealand citizenship and attempt a return by winning back his New England seat.
If the the court rules against the Nationals leader the Liberals' main issue will be how to manage Parliament until a by-election is held. During that period the Coalition would govern by a
PRIME MINISTER BACKS JOYCE
However the prime minister Malcolm Turnbull has backed Mr Joyce, resisting calls from Labor for him to step aside until the High Court examines his status.
And Attorney-General George Brandis declared that he expects the court will clear Mr Joyce.
Senator Brandis told the upper house that there were "factual and legal differences" between the deputy PM's case and that of Cabinet Minister Matt Canavan, who stood down when his dual citizenship was revealed.
Speaking to Sky News, Senator Brandis said dual citizenship may not be a clear-cut breach of Section 44 "in certain circumstances".
"There has to be some conscious acknowledgment… so in a case such as Mr Joyce's, he first learnt of this on Thursday afternoon and it came as a complete shock to him," he said.
Labor has responded angrily to Mr Joyce's declaration that on the basis of legal advice from the Solicitor General, he would carry on as Deputy PM and continue to vote on legislation in Parliament.
Tony Burke, the Manager for Opposition Business, said Mr Joyce must step aside and not vote on legislation until the High Court rules on his eligibility.
"This is a government without legitimacy," Mr Burke said.
The call comes as an overwhelming response to a News Corp Australia poll, participated in by more than 44,000 people, shows the majority of Australians think he should go.
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