Nationals Senator for Queensland, Senator Matt Canavan and Pauline Hanson’s One Nation Party Senator for Queensland, Senator Malcolm Roberts have amended their version of events regarding key details concerning their citizenship status, as the High Court began hearings on the case that could have ramifications for the Prime Minister and the 45th Parliament.

As one of seven Parliamentarians currently under a cloud, Senator Canavan had previously indicated he was an Italian citizen thanks to his mother’s paperwork when she herself commenced her own documentation process. However on Thursday it was revealed, via Senator Canavan’s legal team, that he had been an Italian citizen since the age of two.

Complicating his own situation, Senator Roberts appeared to admit that he had actually not filled in his British citizenship renunciation documents until after he was elected.

Compounding the worry for the Government, the High Court, sitting as the Court of Disputed Returns, did not acquiesce to a request by the Attorney-General, Senator the Hon George Brandis QC, for a September hearing into the validity of the Parliamentarians. The case will now be heard in Canberra over three days from October 10, further prolonging the uncertainty surrounding prominent Parliamentarians including the Deputy Prime Minister, the Hon Barnaby Joyce MP.

Nationals Minister and Deputy Leader of the Party, Senator the Hon Fiona Nash and crossbench powerbroker, Senator Nick Xenophon, will have their cases referred when the Senate resumes on September 4.

Solicitor-General, Dr Stephen Donaghue QC, for the Attorney-General, signalled he would argue Minister Joyce and Senator Canavan were not disqualified from Parliament, and former Senator Waters “may well be in the same situation” but there was no dispute that former senator Ludlam was disqualified and there would be a contest over Senator Roberts’ ability to remain in Parliament.

Dr Donaghue said there was a “clear demarcation line” between politicians such as Mr Joyce, who had not known they were foreign citizens, and those such as Senator Roberts who had been aware of their foreign citizenship.