The federal government has failed to secure Labor’s support for new measures requiring politicians to disclose their citizenship status to parliament, but talks are still underway.
Labor has called for tougher rules on citizenship disclosures by MPs and Senators, slamming the government’s proposed changes as “half-baked”.
The government wants all politicians to issue a declaration to the Register of Members’ interest outlining their belief they are not dual citizens.
All MPs and senators would have to formally declare they are not dual citizens to that parliamentary register, as well as providing details about where their parents were born.
Politicians who were once foreign citizens would also need to provide proof they had renounced.
But the opposition says politicians simply having a belief of their citizenship status is not enough, as well as calling for politicians with foreign-born parents to do more checks.
Opposition Leader Bill Shorten says the 'I didn’t know' defence isn’t appropriate.
“If you know that your parent was born overseas, what steps have you taken to find out that the law overseas in that country doesn't confer citizenship upon you,” he said.
“Labor is not going to support watering down the High Court decisions to help a few MPs scrape back into parliament.
“We don't want a half-baked solution.”
Labor also wants the issue resolved sooner, saying the disclosure should be submitted no later than December 1.
“We want to sharpen up the prime minister’s resolution and make sure it’s fool proof.”
The comments came after Mr Shorten met Prime Minister Malcolm Turnbull to discuss a bipartisan solution to the dual citizenship crisis.
Mr Turnbull said the discussions were constructive and both sides many areas of agreement.
He said there could be a role for the Department of Foreign Affairs to help politicians check their backgrounds.
"That knowledge of that foreign law is going to be critically important for many people. There's a role that the Department of Foreign Affairs can play," he said.
Earlier, Treasurer Scott Morrison said Labor should stop trying to exploit the dual citizenship issue for political gain and instead work with the government to implement a disclosure regime.
"What we've seen from the Labor Party is an attempt just to create uncertainty, to create disruption," Mr Morrison told reporters in Sydney on Wednesday.
"I don't think the Australian public will take kindly to an opposition seeking to be opportunist on this."
SBS World News understands Mr Turnbull would prefer to see the parliamentary disclosures completed this year.
Labor is concerned the government is stalling on the citizenship questions around Liberal MP John Alexander.
Meanwhile, two Labor MPs, Tasmania's Justine Keay and Queensland's Susan Lamb, are also facing questions over possible dual citizenships.
Ms Keay says her renunciation of British citizenship was not effective until after the 2016 election, while Ms Lamb has said she took all necessary steps to renounce her British citizenship in May 2016, but has not said if this was confirmed before the deadline, the Guardian reports.
The recent High Court ruling stated Section 44 "does not disqualify only those who have not made reasonable efforts to conform to its requirements".
John Alexander is seeking advice from UK authorities on whether he holds citizenship by descent through his British-born father - a case virtually identical to that of disqualified senator Fiona Nash and resigned senator Stephen Parry.
He believes he is solely an Australian citizen, but has promised to make a full statement once the advice is received.
Labor says the MP for Bennelong should be referred to the High Court.
However, the prime minister says all MPs should be allowed to make their declarations under the new process and then cases can be referred to the court.
If Mr Alexander is disqualified from parliament, the government - which holds a one-seat majority and is already fighting a by-election in New England - would be forced to a by-election in Bennelong, which the MP holds with a 7.8 per cent margin.
Liberal senator Eric Abetz said he hoped there would only be a "limited number of by-elections", but a general election could not be ruled out.
"If there are a whole lot, who knows what might come about?" he told Sky News.
Former Liberal senator turned independent Cory Bernardi suggested the best solution would be to prorogue the parliament.
"We should be suspending it, no more decision-making to take place until we can prove that everyone is fit and proper and constitutional to be there," he told ABC TV.
"We are on the cusp of a full-blown constitutional crisis and the government is taking steps which will not get to the bottom of it because they rely on the honesty."
- with AAP