Republicans will not be intimidated from "pursuing their legitimate right to end British occupation in our country", the chairman of the 32-County Sovereignty Movement has said.
Addressing supporters at an Easter commemoration in Arbour Hill cemetery, Dublin, Mr Francie Mackey said it was fitting that republicans who upheld the ideals of the 1916 Proclamation should gather at the burial place of the Rising's leaders.
He added: "It is worth noting that the stance they took then was met with demonisation and vilification to discredit the legitimacy of their position, and although small in numbers, they have proven to be correct."
About 200 people attended the commemoration, which took place only hours after a bomb attack in London, attributed by the British police to the so-called "Real IRA".
The attendance included Ms Bernadette Sands McKevitt, who laid a wreath on behalf of the sovereignty movement, and the former IRA hunger-striker, Ms Marian Price, who addressed the crowd on behalf of the republicans of Ulster.
The commemoration began earlier at Liberty Hall, where a youth dressed in an Irish Volunteers uniform read a statement about the events of 1916. The group then marched to the GPO for a reading of the Proclamation, before going to Arbour Hill.
Mr Mackey said the movement's action in attending the recent 57th commission on human rights at the UN and formally protesting against Britain's denial of the Irish people's right to self-determination had brought a "panic reaction" from the Government.
He pledged to expose the Government's "failure to protect the sovereignty of the Irish people".
He added: "This applies also to those who have lost their nerve and have compromised the republican position by accepting an agreement which is contrary to the wish of the vast majority."
Mr Mackey said one of the effects of the Belfast Agreement was to abolish political status for prisoners, leading to a situation in which republicans were forced to integrate with loyalists in the North's Maghaberry prison, at "grave danger" to their personal safety.
This was "a powder keg waiting to explode", he added. "There have been a number of incidents whereby boiling water has been thrown at republican prisoners and broken glass has been found in their food. Republican prisoners are living on a knife edge."
He also condemned the "harsh regime" for prisoners in Portlaoise, "where compassionate parole to visit sick, elderly and dying members of their immediate families is refused".
