After a week that saw deputy PM Barnaby Joyce referred to the High Court over his former New Zealand citizenship, Prime Minister Malcolm Turnbull has been urged to stop parliament from sitting until the Court rules on the fate of Nationals leader.

The ongoing fiasco took yet another dramatic turn on Thursday afternoon, as parliament adjourned for two weeks, when deputy Nationals leader Fiona Nash revealed she was a dual British citizen. Senator Nash said she will not be standing down from her ministerial duties while the Court adds her case to its growing list of referrals. Her UK citizenship is understood to be by descent as her father was born in Scotland.

So far five senators have been referred to the High Court; two have stepped down pending the Court’s ruling, and on Friday Senator Nick Xenophon’s possible British citizenship was called into question. In increasingly partisan behaviour, both the Coalition and Labor have encouraged speculation about their respective overseas-born adversaries as well as MPs and senators who have second-generation ties to other nations.

As media speculation has run rife over the dual citizenship issue, Labor’s line has been to refer to the statement given by ALP national secretary Noah Carroll, that the party’s citizenship checks have always exhaustive “ensuring that every candidate satisfies all constitutional requirements” before nomination, and “where there are any issues with respect to dual citizenship – potential or otherwise – candidates are required to take all reasonable steps to renounce and satisfy the requirements of Section 44.” Mr Carroll added that a candidate would not have been nominated by the ALP without being cleared through this process.

Earlier in the week Leader of the House Christopher Pyne suggested four Labor MPs – Maria Vamvakinou (born in Greece); Tony Zappia (born in Italy); and Justine Keay and Susan Lamb (whose fathers were British), should be referred to the High Court if they failed to provide documentation of renouncing their foreign citizenships. Labour declined the demand but the MPs offered a timeline of their renunciations.

Ms Vamvakinou added more to her public comments on the matter, originally tweeted on 20 July, “I renounced my citizenship in August 2000 and I took all necessary steps to comply with Section 44 of the Australian Constitution”.

The Labor MP tweeted on Tuesday: “On 9 August 2000, I formally renounced Greek citizenship via the Consul General in Melbourne”. The Member for Calwell said she received acknowledgment of her renunciation letter on 21 August 2000.

Crossbench senators including Nick Xenophon have called for an independent audit of all federal parliamentarians to identify potential dual citizens. Both Labor and the Coalition have so far rejected the move.