A dual citizenship dilemma has ended James Harker-Mortlock's campaign for the federal seat of Whitlam.
The Nationals candidate's pre-selection was voided by the party on Thursday, after he was unable to provide proof of renunciation of his British citizenship from the United Kingdom.
Evidence of foreign citizenship renunciation or Australian citizenship must be provided as part of the documentation when a candidate nominates before April 23.
Mr Harker-Mortlock said he was "annoyed and disappointed" he had to step down from his candidacy, which was a mutual decision between the former candidate and the party.
"It was impossible for me to extract that information from the UK," Mr Harker-Mortlock told the Southern Highland News.
"I was unable to sign the nomination form so the Nationals could not endorse me."
Mr Harker-Mortlock, who has been in contact with UK officials and the Department of Foreign Affairs and Trade, said his British passport expired 25 years ago.
The former candidate said section 44 of the constitution in its current form should be repealed or amended.
Section 44 sets out restrictions for any person who is under any acknowledgement of allegiance, obedience or adherence to a foreign power, or is subject to the rights or privileges of a foreign power.
"If we want to be the open, welcoming, multicultural society we say we want to be, we need to recognise there is a large amount of people who will not be able to participate fully in the society to which they have become a member," he said.
Labor candidate Stephen Jones, Greens candidate Jamie Dixon and United Australia Party candidate Angelo Cudo will run for the seat of Whitlam on election day on May 18.
The Nationals have not confirmed whether they have a candidate to replace Mr Harker-Mortlock.
Meanwhile Mr Harker-Mortlock said the decision to step down before the federal election did not spell the end of his political career.
"I won't be able to run this election. Being a campaigner I've done it a few times and I'd never rule out running again," he said.
"As someone who has always enjoyed being involved in political campaigning, I got a particular buzz out of campaigning in Whitlam."