A referendum on a united Ireland could be held before 2016, Sinn Féin’s Conor Murphy has said.
At a public briefing, An Ireland of Equals -- the Peace Process and Beyond, held in the House of Commons, Mr Murphy said that reunification was not a spectator sport.
“We were accused of setting 2016 as the date for the hundred-year anniversary. It may take longer,” he said.
“But I actually think it could happen sooner than that in reality if we keep the momentum going when the economic realities and the political realities hit.
“We have received an awful lot of attention over the last 10 years with American presidents and other nations dropping in but that will start to wane.
“Then we will start to realise we are a small island, we have quite a lot going for us.
“All these small signs show we will ultimately have to take charge of ourselves in the end,” he added.
In a separate development, the 2007 annual population reports, released this week, showed an increase in the birth rate in the Six Counties, from 13.4 births per thousand of population to 13.9.
Some commentators believe the traditionally higher birth rate among Catholics could ultimately lead to a nationalist majority.
There was an overall 1% increase in the population of North, to an estimated 1,759,000.
With the population of the 26 Counties now at 4,422,100 it means the total population of the island is higher than at any time since the Famine.
However, the latest figures also show the population of Dublin will fall in the coming decades for the first time since the Famine if immigrants stop coming to Ireland, as is expected.