A ninth MP has been struck down by the citizenship fiasco that has engulfed the Federal Parliament, with NXT senator Skye Kakoschke-Moore announcing she will resign after discovering that she is a British citizen by descent.

After an exhaustive search to determine her citizenship status, Ms Kakoschke-Moore has confirmed her mother was born British in Singapore at the time it was a colony and that the senator was, herself, a citizen of Britain. MPs are not permitted to be citizens of a foreign nation under section 44 of the constitution.

Ms Kakoschke-Moore, who was born in Darwin and has not previously been connected to the citizenship crisis, said she had believed for her entire life she was not eligible because usually when a parent is born outside Britain they are unable to pass their citizenship on to their children also born outside Britain.

Her father had even made inquiries as to whether she could get a British passport when the family lived in Oman when she was 12 but he was told she was not eligible.