Ms Banks also told Fairfax Media: "I was born in Australia as was my mother. My father was born in Greece. Both my parents were Australian citizens at the time of my birth." Julia Banks won the seat of Chisholm at the 2016 election. Credit:Eddie Jim What is not clear is whether Ms Banks may have had Greek citizenship automatically conferred on her via her father. Legal experts are split over whether the first term MP's status was in question. The MP did not answer when asked if she had formally renounced her entitlement to take up Greek citizenship. Fairfax Media understands that at least one of Ms Banks' siblings has taken up Greek citizenship.

Ms Banks won the marginal seat of Chisholm with 51.2 per cent of the two-party preferred vote at the 2016 election. It was the only seat won by the Liberal Party from Labor in the federal election and the Turnbull government holds power in the lower house by just one seat. Malcom Turnbull and Julia Banks together in the electorate of Chisholm after the election. Credit:Eddie Jim If a byelection was held, Labor would fancy its chances of reclaiming the seat. That would mean the Turnbull government held just 75 seats in the 150-member house and would need to rely on the crossbench, including a number of independent MPs, to hold government. Labor's Victorian headquarters is bubbling with excitement over the Banks predicament. Senior Liberals have expressed concern to Fairfax Media that Ms Banks might be caught up in the growing scandal that has so far seen three senators admit to dual citizenship.

Section 44 precludes people from being candidates for the federal parliament if they are "under any acknowledgement of allegiance, obedience, or adherence to a foreign power, or is a subject or a citizen or entitled to the rights or privileges of a subject or citizen of a foreign power". Greens senators Larissa Waters and Scott Ludlam quit Parliament and the Nationals senator Matt Canavan has quit cabinet, pending the outcome of a High Court case. There are also serious questions facing One Nation senator Malcolm Roberts. In her maiden speech, Ms Banks thanked her late father, Sofoulis Phillip Lolatgis, who "first landed in Australia in 1949 as a 15-year-old migrant boy from Greece" and her mother, who was born in Australia and is of Greek descent. The Greek embassy website states that: "A person acquires Greek citizenship at the time of birth, if said person is born to a parent of Greek nationality – that is, the offspring of a Greek citizen, even if the parent has not exercised his/her right to citizenship". But it also states that "a Greek citizen is a person who is duly registered in the Records of a Municipality of the Hellenic Republic".

Professor Williams said "the question for me is whether you are a citizen of Greece if you are not entered into the roll". "In some countries it's not an issue, you can simply be a citizen. Larissa Waters was caught out without taking any steps [to become a citizen]," he said. "It's a matter for Greek law whether it's enough for her to be considered to have these rights without having taken any steps to be a citizen herself. If that is the case, she would be disqualified even though she has not actually taken any positive steps in that direction herself. "The requirement under Australian law is that she take every reasonable step to divest herself of citizenship rights from another country. And so the question is has she divested herself of those rights if they are conferred upon her?"

A spokesperson for the Greek embassy in Canberra confirmed Ms Banks would have acquired the right to citizenship by blood when she was born – much as Senator Canavan had acquired Italian citizenship – but that it also needed to be "activated". Constitutional law professor Anne Twomey said the High Court had "not expressly dealt with this issue of underlying entitlement to citizenship, so it remains the subject of speculation". "If the entitlement is achieved by virtue of descent, rather than birth, and if an action has to be undertaken to give effect to that citizenship, such as the making of an application, or registration, then I doubt that there is disqualification under section 44 if no such action has been undertaken." Loading Liberal Party president Michael Kroger was not available for comment.