Sinn Fein is to hold major conferences in the US and UK to rally support among the Irish Diaspora for a united Ireland.
At the party's celebrations to mark the Dail's 90th anniversary, president Gerry Adams said the meetings were designed to drum up international support.
The party chief said the Ireland of today was not the state dreamed of by the 1916 leaders as partition had politically and economically stunted its potential.
"There are tens of millions of people across the globe who can proudly trace their lineage back to Ireland," Mr Adams said.
"Sinn Fein will be inviting Irish-America to discuss with us how we can advance a united Ireland campaign.
"Our intention is to engage with the Diaspora and seek to marshal its political strength."
Mr Adams said there was considerable goodwill in the US for a united Ireland and the party would be focusing its efforts this year on the vast Irish/American population.
Two major conferences will be held in the summer, although dates and locations have yet to be finalised.
A third conference is also planned for London early next year, with activists already lobbying Irish communities, MPs and trade unionists across England, Scotland and Wales.
"Now is the time to promote a united Ireland as desirable, viable and achievable in this generation through peaceful and democratic methods," Mr Adams said.
He insisted the party would reach out to unionists to ensure they are comfortable and secure in a new united Ireland.
The party today staged a major event at Dublin's Mansion House marking the sitting of the first Dail.
The Dail was yesterday forced to mark the event a day early because Sinn Fein had booked the venue.
The first parliament lasted just two years and met 21 times in private houses and hotels - always under the threat of police raids.
Sinn Fein won 73 seats in the 1918 general election followed by 26 for unionist parties and six for the Irish Parliamentary Party.
Many of the two million voters were casting their ballots for the first time.
The first shots in the War of Independence were fired on the same day the first Dail sat.
Sinn Fein organised a day-long series of events to mark the momentous occasion, including a photographic exhibition and historical walking tours of the Mansion House and surrounding streets.
The party also published a commemorative pack, to be sent to schools around the country, containing reproductions of the documents adopted by the first Dail.
Mr Adams launched a stinging attack on the Government over its handling of the economy, claiming wealthy bankers and property developers were protected while the old, sick and young had been targeted.
"Sinn Fein warned, time and time again, that this Government was mismanaging the economy," Mr Adams said.
"Let me make it clear: this mess is not the fault solely of Brian Cowen.
"It is the fault of successive governments and taoisigh."