A storm has arisen after IRA veteran and former Sinn Féin assembly member John Kelly criticised the actions of some in the party who he said had attempted to silence and sideline him.
He said he was censured after making efforts to reach out to hardline unionists and republican dissidents.
Mr Kelly stepped down from the party last year, having announced that he would not be defending his seat in Mid-Ulster.
In an interview with the Irish News, he said: I began to feel that within Sinn Féin republicanism there was no room or no space for people to have an opinion that was different from the leaderships opinion.
It was contrary not only to the whole spirit of republicanism, but to the whole concept of the civil rights movement... I thought it was dangerous and unhealthy.
The 68-year-old said political gains had been made through the peace process, but said that creative ambiguity over the IRAs future had devalued the 1998 Good Friday Agreement.
He pointed out that republican campaigns of armed struggle had traditionally ended with those groups dumping arms and dispersing.
Mr Kelly said tensions had been stirred by his decision to pay humanitarian visits to dissident republican prisoners in Maghaberry jail, and by his role in helping to elect DUP veteran Willie McCrea as chairman of the mainly nationalist Magherafelt District Council in line with an agreed powersharing scheme.
Sinn Féin responded in personal terms, accusing Mr Kelly of simply being bitter "in the aftermath of his non-selection as a candidate for Novembers assembly elections.
But in a statement issued yesterday, Mr Kelly stated out that he had been selected, but had later come under pressure to stand aside amid disapproval of his actions. He had subsequently resigned from Sinn Féin.
And it was following that, that Sinn Féin held another convention to elect someone to replace me," he said.
I said I did not intend to be a thorn in the side of Sinn Féin republicanism. And I am saying that I will not allow them to be a thorn in my side by abusing the truth with the dishonest political instrument of creative ambiguity.
I have no trouble moving on, but from the platform of the truth, not the platform of creative ambiguity.
* A court has ruled that Sinn Féin and a former party member should pay 17,500 Euros for an assault on another former member and intimidation of his wife in County Wexford during the last election campaign.
Sinn Féin has claimed its Wexford branch was infiltrated by Fianna Fail supporters with a view to causing trouble.