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 one-seat majority.

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.

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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 63,000 people, shows the majority of Australians think he should go.

Vote in our poll below.

“Last Thursday afternoon the New Zealand High Commission contacted me to advise that on the basis of preliminary advice from their department of internal affairs, which had received inquiries from the New Zealand Labor Party, they considered that I may be a citizen by descent of New Zealand,” Mr Joyce told Parliament this morning.

“Needless to say, I was shocked to receive this information. I have always been an Australian citizen, born in Tamworth, just as my mother and my great-grandmother (were) born there 100 years earlier.

“Neither I, nor my parents, have ever had any reason to believe that I may be a citizen of any other country.”

The Government holds a one-seat majority in the House of Representatives. Under section 44 of the constitution, being a citizen of another country makes one ineligible to hold elected office.

If Mr Joyce was disqualified from being able to sit in Parliament, the government would lose its majority.

The Prime Minister defended Mr Joyce during a fiery Question Time.

“If an Australian citizen, who became a citizen of this country by reason of being born here, was to be ineligible to stand for Parliament because the law of a foreign country imposed foreign citizenship on them without their knowledge, due to their descent from a parent, grandparent, great-grandparent, then, plainly, millions of Australians could be disqualified from standing for parliament,” Mr Turnbull said.

“Based on advice from the Solicitor-General, the government is very confident the court will not find that the member for New England is to be disqualified from the Parliament.”

Labor made a bid to prevent Mr Joyce speaking in Question Time, moving a motion that he no longer be heard just seconds into the deputy PM’s first attempt to answer a question.

A poker-faced Joyce sat through the session as Labor fired question after question about his citizenship and right to sit in Parliament at the Prime Minister.

When he was finally able to rise to his feet, Mr Joyce was heckled by Labor backbenchers who ‘baa-ed’ at him.

Read more: The Barnaby Joyce citizenship saga explained

"Unwittingly or not, he's a New Zealand citizen" - NZ Prime Minister Bill English confirms @Barnaby_Joyce is a citizen by descent #auspol — Jane Norman (@janeenorman) 14 August 2017

‘FIFTH GENERATION AUSTRALIAN’

Mr Joyce, who was born in Australia in 1967, said he considered himself a fifth generation Australian.

However his father was born in New Zealand and came to Australia in 1947 as a British subject, as New Zealand and Australian citizenship was not officially created until 1948.

“If you were born overseas and at least one of your parents is a New Zealand citizen by birth or grant, you are an NZ citizen by descent,” the New Zealand Government website on citizenship

and passports states.

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However Mr Joyce disputed this in Parliament, saying the New Zealand Government had no register legally recognising him as a citizen.

“Given the strength of the legal advice the government has received the Prime Minister has asked that I remain Deputy Prime Minister and continue my ministerial duties,” Mr Joyce told Parliament.

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Mr Joyce’s case was referred to the High Court by Turnbull Government Minister Christopher Pyne.

While making the referral, Mr Pyne told Parliament: “It is time for the High Court to be given the opportunity to make a determination about what section 44(1) of the Constitution means in the modern era.”

“Because we are so confident of the deputy prime minister’s status, he will continue fully, fully as the Member for New England, participating in the House and as the deputy prime minister and the Minister for Agriculture and Water Resources,” he said.

Treasurer Scott Morrison downplayed the threat to the Turnbull Government’s majority.

“You don’t leap to conclusions about this and you do what is appropriate and that is what the Deputy Prime Minister and the Prime Minister has done,” Mr Morrison told reporters at Parliament.

“You simply take the next step. It doesn’t distract the Government from what we are focused on.”

There were also fresh questions today over the citizenship status of Labor MPs, including Anthony Albanese and Tasmanian MP Justine Keay.

At a press conference in Canberra, Mr Albanese denied there were any question marks over his status.

“The circumstances of my birth is that I had a single parent, there is a single parent legally on my birth certificate, that was my mother who was born ... in the same hospital in which I was born in Darlinghurst (in Sydney),” he said.

“Her parents were both born here. Their parents were all born here as well.”

Ms Keay’s eligibility is in doubt as she only received confirmation that her UK citizenship had been renounced on July 11 last year, a week after the federal election.

But as she had written to the UK Home Office renouncing her British citizenship on May 23 and the form was received on May 31, she might be covered under the requirement that candidates for election make “all reasonable steps” to renounce their dual citizenship.

The latest saga comes on the back of two Greens MPs resigning over holding dual citizenship, and Nationals MP and Cabinet Minister Matt Canavan and One Nation Senator Malcolm Roberts being referred to the High Court.

The office of Queensland Liberal MP Bert van Manen, who is automatically eligible for Dutch citizenship by descent, confirmed to News Corp Australia his citizenship would not be referred to the High Court.

Good news for Barnaby Joyce: in NZ he can marry whomever he likes. — Daniel Carosone (@redtwitdown) August 14, 2017

Mr van Manen had received confirmation from Dutch authorities that he did not hold citizenship.

Another Liberal MP, Jason Falinski, has also confirmed that he is not a dual citizen by descent.

Mr Falinski confirmed with Polish authorities last month that he did not hold citizenship.

The Prime Minister has written to Opposition Leader Bill Shorten to invite him to “nominate any Labor members of senators whose circumstances may raise questions”.

In a reply shared on social media, Mr Shorten said Labor had “the strictest processes in place” and he would “politely decline” the request.

A TIMELINE OF CHAOS

Greens deputy leader, Senator Scott Ludlam resigned on July 14. He had dual citizenship of Australia and New Zealand.

Under section 44 of the constitution, that makes him ineligible to hold elected office.

Greens deputy leader Senator Larissa Waters quit on July 18. She is a dual Canadian citizen.

Coalition MP Resources Minister Matthew Canavan quit on July 25. His mother had applied for Italian citizenship for her son and herself in 2006 without his knowledge.

One Nation has referred Senator Malcolm Roberts to the High Court for a decision on whether he was a dual British and Australian citizen when he nominated for Parliament.