ANTI-agreement republican party Saoradh has said it rejected an attempt by Sinn Féin to "develop a common strategy and co-operation" for Irish unity.
Saoradh, which has the support of New IRA prisoners, last night confirmed it was approached in writing by Sinn Féin in November 2020.
Details of Sinn Féin's attempts at reaching out were first reported yesterday in The Sunday Times.
In a letter Sinn Féin national chairman Declan Kearney invited the hardline republican party to take part in talks about a united Ireland.
In the past the party has been critical of dissident republican groups who continue to oppose the 1998 Good Friday Agreement.
Mr Kearney's letter, which was addressed to the Saoradh party chair and sent to its Derry headquarters, came just over 18 months after the New IRA shot dead writer Lyra Mckee in the city as she observed a riot in the Creggan estate.
In his correspondence Mr Kearney, who is a former Stormont junior minister, said the "imposition of Brexit and its implications for Ireland underlines the enduring undemocratic nature of partition".
He added that the Covid pandemic "has brought the contradiction of our country's division into even sharper focus".
The senior Sinn Féin politician added that the "prospect of securing a referendum on Irish unity is very real but we must make it a reality".
"Winning a unity referendum on Irish unity will bring a new momentum to the achievement of a national republic," he wrote.
"Sinn Féin believes such a referendum should be an immediate political priority for all republicans, progressives and democrats."
Mr Kearney said his party is "committed to encouraging an inclusive, popular debate in Ireland about how a transition to national unity can be organised, and on the type of constitutional, political and civil rights and guarantees which citizens should enjoy in a unitary state".
"In order to promote engagement on developing common strategy and co-operation towards achieving that outcome I invite you and a delegation from your party to meet with myself and other members of the Sinn Féin leadership."
Saoradh spokesman Paddy Gallagher said his party remained opposed to the Sinn Féin position as its "current political outlook has led them into a strategic cul-de-sac of collaboration that has actually consolidated partition."
Mr Gallagher added that it has "no interest in engaging in private dialogue".
"Saoradh are on public record stating that public debate, rather than private dialogue, is the best place to gauge differences in the core positions between republicans and constitutional nationalism as led by Sinn Féin," he said.
It is understood that in the past Sinn Féin has also written to various other anti-agreement groups.
Its members have also taken part in public debates as part of the IRSP established 'Yes for Unity' campaign.
Republican Sinn Féin sources last night said it also had received similar correspondence from Sinn Féin but, despite being contacted yesterday, the party did not respond.
