Matt Canavan says he considered quitting the Upper House when he found out he was an Italian citizen — but has defended his decision to fight for his right to stay in the Senate.

Key points: Senator Canavan says he has advice he is not in breach of the constitution

Senator Canavan says he has advice he is not in breach of the constitution He will not release paperwork supporting his case at this time

He will not release paperwork supporting his case at this time Deputy PM has taken over his ministerial role pending court case

Unlike the two Greens caught in the constitutional crosshairs by their citizenship he will ask the High Court to rule that he is still eligible to be in Parliament.

Senator Canavan said he has legal advice that he is not in breach of Section 44 of the constitution.

The basis of his case will be that he cannot take any steps to renounce citizenship he did not know he had because his mother filled in forms without his agreement.

"I have never signed a document or given a consent or had any knowledge of these matters until the last week," Senator Canavan told the media in Rockhampton today.

"It is pretty tough for my family but I would not be doing this without the support of my family.

[I'm] very fortunate to have a strong and resilient family.

"Times like this make you realise how important families are, so we are sticking together.

"My mum acted in what she thought was my best interests and had no idea of the constitutional ramifications of any of this until the matters involving the two Greens senators were in the media in the last couple of weeks."

But he said he was not prepared to release the documents showing the papers his mother filled in.

"These now will be matter for the court to look at and it is not appropriate to run these conversations through the media," Senator Canavan said.

"They will all be revealed — there will be a time and a place for all this now once it goes before the court."

Canavan denies receiving Italian paperwork

There are reports that Italian authorities have sent mail to him in Australia since he became a citizen in 2007, but Senator Canavan denied receiving any.

"I have not received any correspondence — from Italian authorities ballot papers other correspondence or anything," he said.

Who is Matt Canavan? A young, conservative minister seen as a rising star of the National party and a close ally of Deputy Prime Minister Barnaby Joyce. The 36-year-old Queensland senator was elected in 2013 and promoted to cabinet after the 2016 election. He's been a tireless advocate for the proposed Adani coal mine. He's a former executive at KPMG, an economist at the Productivity Commission and a chief of staff to Mr Joyce. Earlier this year he criticised Westpac bank's decision to refuse finance for mining projects in the Galilee basin, where the Adani mine would be based. Senator Canavan has repeatedly called on states to end state bans on gas exploration and extraction, accusing them of undermining energy security.

When it was suggested they had gone to his mother's address, he said he had not viewed any himself.

Greens leader Richard Di Natale argued Senator Canavan should resign from the Senate as well as from Cabinet.

But he defended his actions, saying it is appropriate to resign his ministry while the matter is cleared up in the court.

The case will be vital to determining Senator Canavan's political future, but he said it has broader implications.

"It will establish principles that go to the heart of eligibility of many Australians to stand for Parliament," he said.