Four non-government MPs have announced their resignation from parliament due to questions surrounding their citizenship status.

The resignation of the Nick Xenophon Team Rebekha Sharkie, and Labor’s Josh Wilson, Susan Lamb and Justine Keay follow the High Court’s ruling that Labor senator Katy Gallagher must step down due to her not renouncing her dual British/Australian citizenship before the last election.

No coalition MPs have been impacted by this latest ruling, however the Opposition has raised questions about the citizenship status of some members, which if true could imperil the government's one seat majority.

There is expected to be a super Saturday of by-elections across the country in late June for the four seats vacated by the ongoing citizenship saga plus a fifth in the seat of Perth due to Labor MP Tim Hammond resigning due to personal reasons.