Sinn Féin president Gerry Adams is continuing to legitimise the abduction and killing Jean McConville by the IRA, Fianna Fáil party leader Micheál Martin said on Monday.

Mr Martin said that those responsible for the death were “still being protected by a movement that Gerry was a member of”.

During a 10 minute radio debate, the party leaders clashed on a number of topics, including “legacy” issues for each party.

Mr Martin said that as long as Mr Adams was in public life he would challenge the Sinn Féin leader of the death of Ms McConville and said it was time Mr Adams dealt with the substance of the issues.

“I will never allow you, Gerry, to whitewash away the atrocities committed by your movement,” he said.

“In terms of legacy, I wasn’t responsible for the murder of anybody. I don’t have to legitimise the murder of anybody,” Mr Martin said.

Mr Martin said Mr Adams has been continuing to promote and protect the idea that the provisional IRA campaign was legitimate.

Fianna Fáil leader claims Mr Adams used the tactic all the time: “he attacks the messenger but doesn’t deal with the substance of the argument”.

Mr Martin said he accepted his party had made mistakes while in government between 2007 and 2011 but claimed Mr Adams did not accept he had done anything wrong in the past.

When Mr Adams was asked on RTÉ's Morning Ireland if Ms McConville's murder was a war crime, he replied that he did not want to debate "emotive" issues as it would be unfair to do so.

Mr Adams said Mr Martin’s attacks were a sign of the “desperation” of the Fianna Fail party at the growth of Sinn Féin in the polls.

The Sinn Féin leader said he was “hugely critical” of aspects of the IRA’s campaign, including the murder of Jean McConville.

“War should not be glamorised. War is desperate,” he said.

Mr Adams said people were left with Fianna Fail’s legacy of the banking debt that tax payers had to pay.

“The brown envelope culture, the Galway tent,” he said.

Mr Adams said he rejected Mr Martin’s claim that Sinn Féin were trying to take ownership of 1916, the party were trying to “popularise it”.

“Even if Fianna Fáil didn’t exist, even if Sinn Féin didn’t exist, 1916 and the centenary is going to be mighty because patriotic people want to commemorate, to celebrate and also to see the unfulfilled promise of the Proclamation fulfilled in our time,” he said.