Liberal Stephen Parry will 'resign as senate president' if he's a British citizen

Senate President Stephen Parry will quit parliament if British authorities confirm he is a dual citizen through his UK-born father.

The Liberal senator from Tasmania has been informed he may hold dual Australian-British citizenship, making him the eighth member of parliament ensnared in the citizenship saga.

Senator Parry said that after the unanimous ruling handed down by the High Court last Friday, which disqualified five parliamentarians, he had examined his citizenship status.

His father moved to Australia as a boy in 1951 and he was born in Tasmania in 1960.

Senator Parry said he always regarded his late father as Australian, particularly as he undertook national service, was a member of the Australian Army Reserve and voted in every Australian election since adulthood.

"Yesterday I wrote to the British Home Office seeking clarity as to the status of my citizenship with the United Kingdom," Senator Parry said in a statement on Tuesday.

"This was the first opportunity to do so since the High Court ruling."

The British Home office has sought further details from Senator Parry, which he provided and was now awaiting a response.

He may seek further legal advice before reporting to the Senate.

"In the event that I am found to hold British citizenship by virtue of my father's status, then I will clearly be in breach of Section 44(1) of the constitution and would therefore resign as President of the Senate," Senator Parry said.

"I would further resign as a senator for the state of Tasmania and not await the outcome of any referral to the High Court, as I believe the High Court has made it abundantly clear what action is required."

According to The Australian, Senator Parry sought confirmation of his citizenship status from the British authorities following last week's ruling that five of his parliamentary colleagues were found ineligible to hold office under section 44(i) of the constitution.

• 'Expect more': Man behind citizenship seven

Last week the man who sparked the chain of events that led to the downfall of Deputy Prime Minister Barnaby Joyce and others said others would likely be caught out in the crisis.

The High Court last Friday threw out all but two of the Independent, Liberal, Greens, Nationals and One Nations MPs.

Only Mr Canavan and South Australian Senator Nick Xenophon survived the challenge.

West Australian Lawyer John Cameron ousted Greens MP Scott Ludlam as a New Zealand citizen in July this year, leading to an eventual constitutional crisis for the Turnbull government.

"There will be others," Mr Cameron told AAP, just hours after the Australian High Court disqualified Mr Joyce and four other MP's on Friday afternoon.

"This opens up a huge can of worms," he said from Perth.