Up to 400 former IRA prisoners are to sign a letter urging republicans to vote against Sinn Féin in this week's elections.
With the race for office entering its final few days, disaffected supporters want rank-and-file voters to punish Gerry Adams' party for its future endorsement of policing.
The polls open on Wednesday with Sinn Féin hoping to share power in a devolved Assembly in Belfast with the Rev Ian Paisley's Democratic Unionist Party.
Former prisoner Danny McBrearty, a long-time critic, said: "The movement has been dismembered by the current leadership. We are asking people to open their eyes.
"It is a total capitulation of what the last 30 years was about, what was the armed struggle about, why did hundreds of out patriot dead die?
"For Gerry Adams and his leadership to enter Stormont, which they told us they would never do. They told us that they would never give a bullet or an ounce, now there's not a bullet or an ounce left."
Those opposed to Sinn Féin's strategy have accused the leadership of heavy-handedness and bullying tactics.
Mr Adams has appealed for dissident republicans to engage with his team.