Tony Abbott's eligibility to be in parliament could come under the spotlight if the Senate supports a review sought by independent senator Derryn Hinch.
Senator Hinch flagged the inquiry during a debate on Monday on referring former Family First senator Bob Day's eligibility to the High Court.
While Mr Day's case relates to whether he received a financial benefit from the commonwealth, Senator Hinch told parliament he was concerned about another point of ineligibility - dual citizenship.
"I foreshadow I will lodge a notice of motion that there should be a review of all senators' and members' eligibility based on their citizenship at the time they were elected this year and at previous elections," Senator Hinch said.
Although he did not specifically mention Mr Abbott on Monday, the Victorian senator wrote an article on his blog in August questioning the former prime minister's eligibility.
Mr Abbott was born in England, held a British passport as a university student and has held an Australian passport since 1981.
When the issue came up two years ago, Mr Abbott's office issued a statement saying: "The prime minister is an Australian citizen and does not hold citizenship of any other country."
Senator Hinch said on his blog Mr Abbott should produce a dated copy of his British citizenship revocation, which would confirm whether it was revoked before his election as an MP in 1994.
The issue of dual citizenship has claimed the seats of several members of parliament, including former One Nation senator Heather Hill, Liberal MP Jackie Kelly and Nuclear Disarmament Party senator Robert Wood.
