Members of Republican Sinn Féin are suffering harassment at the hands of Sinn Féin and the IRA, the president of Republican Sinn Féin, Mr Ruairí Ó Brádaigh, has told his party's annual conference.
Efforts to raise money "across the six counties" for the families of republican prisoners linked to Republican Sinn Féin who are held in Maghaberry Prison have run into difficulties.
Hotels and pubs that had initially agreed to host fundraising functions "in aid of prisoners' dependants are intimidated by former comrades and forced to refuse bookings", Mr Ó Brádaigh.
"What will the situation be when the Provos don the uniform of the British police in Ireland?" he went on, pointing to the attacks ordered by Éamon de Valera on republicans during the 1930s and 1940s.
"The example of Broy's Harriers, who consisted in the main of former IRA volunteers, gives us a clear indication of what to expect. They will enforce British rule with gusto as they hound former comrades who continue the struggle."
The security forces north and south of the Border, he said, are engaged in "a campaign of harassment, smearing and felon-setting, with occasional show-trials" to retard the development of his party, he said.
The trial of the head of the "Real IRA", Michael McKevitt, who was convicted in August on a charge of directing terrorism, was "a well-publicised show-trial", Mr Ó Brádaigh declared.
"He was sentenced to 20 years' imprisonment on the word of a paid agent-provocateur employed by the US Federal Bureau of Investigation and the British security services."
The main witness, Mr David Rupert, Mr Ó Brádaigh alleged, had promised "an unlimited supply of dollars" to Republican Sinn Féin if it "amalgamated with the 32-County Sovereignty Committee".
He added: "Republican Sinn Féin feels vindicated in its decision, on ideological grounds, to reject Mr Rupert's demands and his money, and to have nothing to do with him," he said, to cheers from ardfheis delegates.
Mr Ó Brádaigh condemned last month's statement by the president of Sinn Féin, Mr Gerry Adams, for saying that Republicans "are opposed to any use or threat of force for any political purpose".
"Republican Sinn Féin bases its stand on the fact that Ireland is a sovereign nation, and sovereign nations the world over have the right to defend themselves and to resist foreign aggression.
"We state further that there will be no full and final closure to the conflict between Irish republicanism and English imperialism and colonialism until the British government signals to the world its intention of leaving Ireland forever."
Meanwhile, he blamed the Irish Government for putting pressure on the GAA to drop its Rule 21, which prevented members of the North's security forces from joining the association.
He said Republican Sinn Féin would never accept the PSNI.