Former Ulster Unionist Party member Earl Storey noted he had long been critical of the republican leadership, in many ways, but he was impressed when invited to the gathering at the Guildhall, in Londonderry - where people were given the opportunity to engage with Gerry Adams, Martin McGuinness and others.

Sinn Fein's leadership has often been accused of a Stalinist approach to internal party debate and of stifling criticism.

People who have left the party have said the leadership does as it wishes.

But the at the Guildhall event, some 500 people were invited to question Sinn Fein policy, from the floor.

Mr Storey, who works for a Church of Ireland reconciliation group, Hard Gospel, said more parties should actually follow the Sinn Fein example and invite criticism of their policies.

Sinn Fein critics have claimed the party holds such events for PR purposes, rather than to necessarily consider changes in policy or direction.

But Mr Storey felt there was an open and honest debate.

He said: "This is a political party I've publicly had critical things to say to over the past, but I was interested in that the meeting actually happened, and that a panel of people invited criticism.

"I thought that was a process I'd like to see replicated in other parties - that sort of public discussion."

At the meeting, Mr McGuinness said no group has the right to drag the community back into conflict, while outlining the party leadership's analysis of the political way forward.

"It's not easy, it's not going to be easy in future, but this is the only road to go," said Mr McGuinness of the political process and devolution.