Labor senator Katy Gallagher has insisted she is not a citizen of Ecuador, rejecting allegations in a Daily Telegraph report.
The report revealed the senator's British mother was born in the South American nation, according to her incoming passenger card.
But Senator Gallagher said her mother's birth and citizenship had been investigated by the Labor party. It was determined she had not obtained Ecuadorian citizneship by descent, she said.
"I am not and have never been an Ecuadorian citizen," the senator wrote in a statement.
Article 7 of Ecuador's constitution states anyone born in the country is an Ecuadorian citizen, as are their children.
But Senator Gallagher said the 2008 Constitution was not in effect when her mother was born in 1943.
Her mother was born to British parents while they were temporarily working in Ecuador.
Turnbull Government frontbencher Michael Sukkar said the Coalition would respect Senator Gallagher's version of events, but criticised Labor's handling of the dual citizenship saga.
"I think you have to take each individual on face value and if she says that she’s certain she’s not an Ecuadorian citizen we take her on face value," Mr Sukkar said.
"But I think this is a pattern of behavior from the Labor Party, where they just seek to shut these questions down."
The dual-citizenship scandal has seen a large number of senators and MPs referred to the High Court, including the deputy prime minister Barnaby Joyce.
Under section 44 of the Australian constitution, a person is incapable of being elected to the parliament if they are a "citizen or entitled to the rights or privileges of a subject or a citizen of a foreign power".
Mr Joyce will be among five politicians facing a High Court hearing from October 10-12.
The deputy PM will be joined by his Nationals colleague senator Matt Canavan, former Greens senators Scott Ludlam and Larissa Waters and One Nation senator Malcolm Roberts.
When parliament resumes crossbench senator Nick Xenophon and Nationals senator Fiona Nash will also be referred to the High Court, and their cases will most likely be wrapped into the same hearing.
