A SECOND Australian senator in less than a week has said she is quitting parliament after discovering she was a dual national and had therefore never really been elected.

The controversy has raised questions about how many other politicians might also have no right to be there.

Larissa Waters, co-deputy leader of the Greens party, said she was quitting after six years as a senator after the Canadian High Commission in Canberra told her on Monday that she was Canadian.

On Friday, the Greens’ other co-deputy, Scott Ludlam, revealed that he was a citizen of New Zealand as well as Australia, which made him ineligible for the Senate job he has held since July 2008.

Australia’s constitution states that a “citizen of a foreign power” is not eligible to be elected to parliament.

Waters, who in May became the first politician to breastfeed in parliament, was born in the Canadian city of Winnipeg on February 8, 1977, to Australian parents. She moved to Australia before her first birthday.

Waters said she thought she had an option of becoming a Canadian citizen and did not take it. She has since found that the law changed a week after she was born, meaning she automatically became a Canadian unless she took steps to prevent it.

Waters said other foreign-born politicians among the 226 in parliament could find themselves in a similar predicament.

“There are many politicians in the Senate and the federal House of Representatives that were born overseas and it may well be that others have to make this embarrassing revelation as well,” an emotional Waters told reporters.

“But I can hold my head up high knowing that the moment I found out, I have taken the step of announcing that I will sadly have to resign,” she added.

Ludlam and Waters could be forced to repay their salaries, with the former reportedly paid more than 1.6 million Australian dollars (£966,000) during his nine years in office.

The Greens are likely to retain all eight Senate seats and their balance-of-power.