The former Alliance Party MLA Trevor Lunn has joined the non-profit campaigning group Ireland’s Future.
Mr Lunn, who now sits as an independent MLA in the Stormont Assembly, will join the group’s Research and Publications section.
Ireland’s Future describe themselves as a group to advocate for and promote, debate and discussion about Ireland's future, including the potential of “new constitutional arrangements”.
Mr Lunn has previously called on the Irish government to talk more openly about Irish unity and described himself in 2020 as an “undecided citizen” on the question of constitutional change.
Making the announcement he was joining the group on Friday, the former Mayor of Lisburn and MLA for Lagan Valley said: “I have worked alongside Ireland’s Future for some time now and admire the respectful and inclusive approach they bring to their work.
“I am prepared to play my part in the developing conversations around possible constitutional change on the island, recognising the need to involve all shades of opinion and to listen to all views.
“We need a constructive debate across Ireland, North and South to establish the best way forward for both populations. I hope I can contribute to that debate.”
Mr Lunn left the Alliance Party in 2020 over what he described as an "irreconcilable internal problem".
Mr Lunn (73) has been MLA for Lagan Valley since 2007.
In the 2017 Assembly election, he received over 6,000 first preference votes, the third highest in Lagan Valley.