Fianna Fail leader Micheal Martin has claimed Sinn Fein leader Gerry Adams had to defend murder.

In a scathing debate between the two on RTE Radio, Adams insisted Martin only mentioned the north of Ireland when he was making a cheap shot against Sinn Fein.

“I've been making these points consistently over the last four years and the point I would make to Gerry very simply, ‘Gerry, in terms of legacy, I wasn't responsible for the murder of anybody.

“I don’t have to legitimize the murder of anybody. You do. And you continue to do it. And to the day I leave public life, I will never allow you Gerry to wash away the atrocities that were committed by your movement.”

Earlier in the radio program Adams was asked if he had any regrets telling an American media outlet that the abduction and murder of widowed mother-of-ten Jean McConville was something “that happens in war.”

McConville was dragged away from her home in Belfast by an IRA gang of up to 12 men and women in 1972.

Adams would not answer the question directly -- and used the opportunity to hit out at Martin. He said if they were going to talk about history then listeners should be reminded of Martin’s 14 years in government when the state was bankrupted and there was a “brown envelope” culture.

The clash followed a claim by the Fianna Fail leader on Sunday at his party’s annual Arbour Hill commemoration of the Rising. He told followers there that Sinn Fein remained unfit for participation in a democratic republican government.

Martin accused Sinn Fein of engaging “in a deeply sinister attempt to misuse the respect which the Irish people have for 1916.”

He said, “Provisional Sinn Fein and the Provisional IRA have no connection with 1916. To claim otherwise is a dangerous and cynical lie.”

Adams dismissed the remarks, and said the claim that his party “is not fit for democratic government is a matter which the electorate will decide.”

Adams said in a statement, “Sinn Fein has a mandate in both parts of this island. That is what drives the hysterical rant by Michael Martin about Sinn Fein at Arbour Hill. His remarks are a clear sign of desperation at the growth of Sinn Fein and the stagnation of his own party.”