Nick Xenophon Team senator Skye Kakoschke-Moore has announced she will resign after discovering she is a dual citizen.
On Wednesday, Kakoschke-Moore said she was “heartbroken” to learn she is a British citizen by descent.
Her mother was born in Singapore while it was still a British colony.
She is the third politician from the Nick Xenphon Team to be caught up in the debacle.
Two Australian government MPs and now seven senators have been forced to leave parliament in the last five months because they were dual citizens, in breach of the Constitution
Earlier this month lower house MP Rebekha Sharkie revealed her UK citizenship was not formally renounced until after nominations for 2016 election.
Former senator Nick Xenophon was referred to the High Court over his UK citizenship but was ruled eligible to stand.
In October, Xenophon resigned from the Senate to return to state politics. At the time he denied that his resignation was related to the dual citizenship case.
On Monday, Prime Minister Malcolm Turnbull cancelled next week’s sitting of the House of Representatives, delaying it for a week in a bid to deal with the widening dual citizenship case.
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