Northern Ireland's Protestant first minister called on Friday for the Irish government to apologise for its role in the emergence of the Irish Republican Army in the 1970s.
The Irish government never backed the paramilitary tactics of the Provisional IRA, but pro-British unionists accuse it of failing to crack down on the group's activity in the Republic of Ireland in the decades before its ceasefire in 1997.
"There is a clear connection between what the IRA did in its infancy and the government of the Irish Republic," First Minister Peter Robinson, head of the Democratic Unionist Party (DUP), said in an interview with the BBC.
"I think the Irish Republic would do well to look at its role and recognise that it was not the way it should have behaved in those days, and apologise for it because massive death and destruction followed," he said.
Relations between London and Dublin have improved sharply in recent years, but some hostility remains between the leadership of the unionist community and the Irish government.
A 1998 peace agreement paved the way for the disbandment of the IRA and a compulsory power-sharing government of unionists and pro-Irish nationalists after a conflict that killed around 3,600 people, many killed by the IRA - known as the Provisional IRA to distinguish it from an earlier Dublin-based group.
The peace deal mostly ended the cycle of violence, though some small armed groups remain and street violence occasionally breaks out between members of the two communities.
The DUP said in a statement that it would put forward a motion in Northern Ireland's regional administration on Monday to ask for an apology from the Irish government.
Robinson, whose party shares power with Sinn Fein, the former political wing of the IRA, made his call after relatives of a notorious IRA attack asked the Irish Prime Minister Enda Kenny to apologise for not doing more to solve the crime.
Relatives of 10 Protestant textile workers killed in 1976 near the Northern Ireland village of Kingsmills, county Armagh, met Kenny on Thursday, but said he told them he could not apologise for the actions of the IRA.
Kenny said in a statement that he told the victims' relatives that the IRA were the "common enemy of all of the people of Ireland". The statement did not mention an apology.
A government spokeswoman said she did not immediately have anything to add to the statement.