Stephen Parry will resign after confirming he is a British citizen.
Senator Parry said he would quit immediately and clear the way for a replacement to be named.
His successor is likely to be former Tourism Minister, Richard Colbeck.
In a message sent to Senators on Wednesday afternoon, Senator Parry said it was “with a heavy heart I inform you that I have received advice from the British Home Office that I am a British citizen by virtue of my father’s birthplace”.
He described his own departure as “rapid and an unexpected event”.
Here is Senator Abetz’s statement:
“Stephen Parry has been a tremendous servant of the people of Tasmania since 2005 and there are many people, like myself, who are deeply disappointed by the news that he will be leaving the Senate.
“Stephen has not only been a valued colleague but has been an exceptional President of the Senate and Chief Whip before that.
“While this is a disappointing turn, Stephen can find comfort in his stellar list of achievements for the people of Tasmania and for the Parliament.
“Should the same approach be adopted to this vacancy as has been adopted in the other cases, I am confident that Richard Colbeck will return to the Senate.
“Richard has been a dedicated servant of the people of Tasmania and I am confident he would hit the ground running if reelected to the Senate as a part of the Tasmanian Liberal Senate Team.
“While this has been a difficult few days for the Tasmanian Liberal Senate team, we are just as committed as ever to working in partnership with the State Liberal Team to advance Tasmania’s interests.”
Liberal Senator for Tasmania, Jonathon Duniam, has spoken about the resignation of his colleague.
“I am terribly upset for my colleague and friend, Senator Stephen Parry, and his family, seeing him today resign from the Senate in these circumstances,” Senator Duniam said.
“He has been a strong advocate for Tasmania since his election to the Senate in 2004 and earned wide respect from all parties in his conduct as President of the Senate.
“Senator Parry has long contributed as a servant for the state with a long history in public service outside of politics.
“I look forward to working with Richard Colbeck should he return to the Senate after the vacancy is dealt with.
EARLIER: Tasmanian Senator Stephen Parry has reportedly received advice from the British Home Office about his citizenship.
Sources in the Liberal Party have told Fairfax Media Senator Parry received advice on Wednesday and will release a statement this afternoon.
A request for comment has been made to Senator Parry’s office.
On Monday Senator Parry – the Liberal Party's most senior Tasmanian – wrote to the British Government seeking clarification about his citizenship.
It is understood the British Government sent advice to Senator Parry on Wednesday.
The content of the advice is not yet known.
If Senator Parry resigns his vacancy would be filled by former North-West Coast Senator, Richard Colbeck.
On Tuesday evening Mr Colbeck told Fairfax Media he had checked his own citizenship status, which he said was only Australian.
Chief Government Whip and fellow Tasmanian Liberal Senator, David Bushby, has not spoken with his colleague about the citizenship.
A spokesman for Senator Bushby confirmed attempts had been made to make contact.
“Senator Bushby is sincerely hoping that Senator Parry’s circumstances lead to a conclusion that he is not a dual citizen,” he said.
“He has since hearing yesterday’s news sought to speak with Senator Parry but has not yet made contact.”
The spokesman said Senator Bushby was “shocked to hear” that Senator Parry could be a dual citizen and could be ineligible to sit in the Federal Parliament.
“Senator Parry has always been a strong representative of the people of Tasmania and, in more recent years, a highly respected Senate President,” a spokesman for Senator Bushby said.
“As Senator Parry is a previous holder of the position of Chief Government Whip, Senator Bushby has also, from time to time, sought Senator Parry’s counsel when dealing with difficult matters that arise in the course of that position.”
The spokesman said Senator Bushby was only an Australian citizen.
“Since this issue first broke earlier this year, Senator Bushby has reviewed his ancestry to try to identify whether there is any aspect that might trigger any citizenship rights in a nation other than Australia. Fortunately, his efforts did not uncover any aspect of his ancestry that could conceivably do so,” he said.
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