Sinn Fein's Martin McGuinness is to bid to become President of Ireland in a dramatic move that has tonight stunned Irish politics.
The deputy First Minister of Northern Ireland, who is a former IRA leader but who became a champion of the peace process, will be formally endorsed by his party leadership over the weekend.
The decision is already being billed as the republican movement's most audacious political move since IRA prisoner Bobby Sands was elected an MP while on prison hungerstrike in 1981.
It is understood party strategists believe that taking part in the campaign ahead of the October polling day will help raise the profile of Sinn Fein, regardless of the result, at a time when it wants to build on its gains south of the Irish border.
But party leader Gerry Adams said Sinn Fein wanted to provide a real choice in the election for the Irish Republic's head of state and believed Mr McGuinness could be "the people's president".
Mr Adams said: "I believe that this election will give Martin the platform to continue the work which he has led in the North and in the peace process and to put it on a national footing.
"I believe he can be the people's president.
"If elected he will draw the average industrial wage.
"He will dedicate himself to a genuine national reconciliation and the unity of our people.
"He will personify hope in the great genius and integrity of all the people of this island - Catholics, Protestants and dissenters."
The Sinn Fein leader added: "I would appeal, if Martin contests this election, for people to join in this campaign, including people in the North and across the diaspora who are denied a vote at this time.
"The campaign will give citizens the opportunity to make a stand for a better Ireland, for a united Ireland."
Mr Adams said: "Sinn Fein believes that the office of Uachtaran na hEireann has been made more relevant by Mary Robinson and by President Mary McAleese.
"This is a time of great challenge for all the people of Ireland. We need positive but authentic leadership.
"It will be a great honour for me to propose Martin McGuinness to contest this election on a broad, republican, citizen-centred platform."
Mrs McAleese, who is originally from Belfast, defied critics to become a major success as Irish president.
Her period in office was recently capped with the historic first state visit to the Republic by the Queen.
Both heads of state laid wreaths to those who died fighting in British uniforms, plus dead Irish revolutionaries.
The president's successor faces the prospect of following two historic periods of office by Mrs McAleese and, before her, Mary Robinson.
The women are seen to have broadened the role of the presidency to provide a platform for the marginalised and to build bridges between Catholics and Protestants across Ireland, north and south.
Independents Mary Davis and Sean Gallagher officially became candidates on Monday after each secured the necessary support. They are on course to fight it out with frontrunner Labour's Michael D Higgins and Fine Gael's Gay Mitchell.
Sinn Fein secured 14 seats in the Dail (Parliament) in the last general election, more than tripling its strength. It also took 3 seats in the Irish senate.
The support of 20 members of the two Houses is required to mount a presidential bid, but sources confirmed Sinn Fein has secured the necessary additional backing.
Commentators had feared a lack-lustre campaign, but the Sinn Fein move is seen to have cranked-up the contest.
The decision to throw Mr McGuinness's name into the race presents Sinn Fein with the tantalising prospect of the top republican holding the office in 2016, the centenary of Ireland's 1916 Easter Rising against British rule. The party will, however, be billed as outsiders in the fight for the presidency.
But its move comes at a time when Sinn Fein is building its presence across the island and seeking to underline its position as the sole all-Ireland party.
In Northern Ireland it has replaced the SDLP as the lead voice of nationalism and republicanism and has a safe hold on power at Stormont alongside the Democratic Unionist Party (DUP).
That position will not be threatened by the decision to enter Mr McGuinness in the presidential race.
The DUP will have had notice of Sinn Fein's plans and there is a precedent for one of Stormont's two senior office holder's stepping aside.
Mr Robinson left office for several weeks at the height of the scandal sparked by the revelation last year that his wife had an affair with a teenager.
The DUP leader temporarily installed a party colleague in his Assembly post, which was allowed under Stormont rules, before he safely returned to the joint Office of First Minister and Deputy First Minister that he shares with Mr McGuinness.
If Sinn Fein follow the same route they could place a senior member into the top office at the power-sharing Assembly without any disruption to the administration.
Mr McGuinness has become a leading supporter of the peace process and has publicly condemned dissident republicans who continue to launch attacks.
But it is inevitable that his own IRA past will be cited during what now promises to be a electrified campaign.
The senior Sinn Fein representative was imprisoned in the Irish republic in the early '70s for IRA activities and he has confirmed he was an IRA leader in Derry around the time of the British army Bloody Sunday killings of 1972.
Mr McGuinness has gained some unlikely supporters from the unionist community for his work in building the peace process, though others still bitterly oppose his role in government.
But the man who security forces would once have billed as the IRA's most wanted leader, is now seen as a politician who has formed strong partnerships with successive unionist figureheads, helping to replace conflict with cooperation.