An Australian couple has reportedly vowed to file for a divorce to end their 10-year marriage once the Australian government legalises same-sex marriage.

Although happily married and blessed with two young children, Nick Jensen said he and his wife Sarah are prepared to divorce, at least on paper, as their way of protesting such a course of action that their government could take. Jensen made the statement in an article he wrote which was published by the Canberra City News on Wednesday.

Jensen said he and his wife believed that changing the traditional definition of marriage to include same-sex couples threatens the sacred nature of marriage and leaves the door open to polygamy. Jensen is the director of the Lachlan Macquaire Institute, which is in partnership with the Australian Christian Lobby in providing scholarships aimed at developing a Christian mindset to future leaders in government.

"My wife and I, as a matter of conscience, refuse to recognize the government's regulation of marriage if its definition includes the solemnization of same sex couples," Jensen said.

Speaking to the Daily Mail, Jensen clarified that their stance was not directed "against any individuals."

"Ten years ago we made an agreement with the State about what marriage was, and that was that it is a fundamental order of creation and part of God's intimate story for human history, man and woman for the sake of children, faithful for life," he said.

"If the state goes down the line of changing this definition and changing the terms of that contract then that is something we can no longer partake in," he said.

Jensen said legalizing same-sex marriage not only threatens "our most sacred institution and have serious consequences for children who would grow up without a mother or father" but could also lead to more serious problems in the future.

"Once you say that marriage is detached from children, [that it's] just about love, then when three people come to the state and say 'well we're all in love', then the state has no grounds, except unjust discrimination, to say why they can't get married," he argued.

"When [marriage] becomes detached to the child's right to a mother and a father and the sacred institution that it is, then suddenly it becomes meaningless and those boundaries can't be put back in place," he warned.

Jensen acknowledged that he has been criticised for his views but said he is aware that other Christian couples who abhor same-sex marriage are also planning to divorce once Australia decides to legalise such union.

He explained though that their planned divorce is only symbolic and that he and his wife would still live together in the same house and still refer to each other as husband and wife.

"Hopefully we'll be able to explain to our children why we had to make this decision," he said.