Northern Ireland Deputy First Minister Martin McGuinness wanted to do a deal on the North but Sinn Féin leader Gerry Adams “won’t let him”, Taoiseach Enda Kenny has claimed.

During heated exchanges at leaders’ questions Mr Adams claimed the Taoiseach had signed up to a paper that did not mention Acht na Gaeilge, or a Bill of Rights and “which acquiesces to the British government on the use of British national security interests and which also seeks to close down Article Two compliant interests”.

But Mr Kenny accused him of not having the courage to “face up to your political responsibility and do what you have to do” on welfare reform.

He said to the Sinn Féin leader: “We put together a political paper on which agreement can be reached if you had the courage to face it down Deputy Adams.”

He suggested he could say to Deputy First Minister Martin McGuinness: “You have responsibilities.”

Mr Kenny added: “He wants to do a deal but you won’t let him.”

Mr McGuinness later rejected the Taoiseach’s comments as “laughable”.

In a sharp Dáil row over the failure to reach agreement during the Northern Ireland talks last week, Mr Adams said Mr Kenny was “a player” and not a junior partner. Agreement could be reached but “not on a purely British or Unionist agenda. Irish national interests have to be upheld”.

A Civic Forum in the North did not exist, nor did a Bill of Rights or an all island charter of rights and there was no joint North-South committee of the two human rights commissions in place.

He said there was no compliance with the European charter for regional or minority languages in place and an Irish language Act did not exist.

Mr Adams said these propositions were hard won over many years and the the Government “cannot be allowed to acquiesce or dilute these”.

He also said that in the Taoiseach’s presence British prime minister David Cameron told Mr Adams that “he would not be establishing an inquiry into the killing of human rights lawyer Pat Finucane as he’s obliged to do under the Weston Park agreement. Taoiseach you sat silently. Not one word did you utter on that issue.”

But rounding on the Sinn Féin leader, the Taoiseach said: “The fundamental issues is that that executive and the assembly sought responsibilty for devolved authority and got it in respect of welfare reform, in respect of pensions and child support.”

He told Mr Adams: “But you are afraid to face the music and make a choice in respect of welfare reform. So you’re putting off the long day here.”

Mr Kenny insisted: “The paper presented in which I had a central part to play from the Irish Government’s point of view did include a direct and specific passage about the Irish language and about Scot’s Gaelic.”

He told Mr Adams there was significant movement “in respect of the historic investigative unit”.

When the chairperson of the unit was appointed by the two governments he would be able to receive “even the most sensitive documentation from the British government and agencies of the British government , which includes issues like Ballymurphy, and which will include in my view other elements of what not have been produced in respect of Finucane”.

He said the Irish Government would continue to support Northern Ireland. That will amount to €500 million over the next number of years and the British prime minister in his discussions with the First and Deputy First Minister, said: “I’m giving you extra capacity to have access to spending power of almost €1 billion and you said that this was ham-fisted and amateurish and was the worst kind of discussions you were involved in, in all your years.”

Mr McGuinness rejected the Taoiseach’s claim that Mr Adams sought to block a deal during last week’s talks as “laughable”.

In a statement, Mr McGuinness said the statement made by Taoiseach in the Dáil was “a threadbare attempt to excuse his failure and ineptitude in this process”.

“Not only is it completely untrue, it is laughable.”

“Sinn Féin is at one on standing by the agreements, standing by the institutions and standing up for the most vulnerable in our society, north and south.

“The joint paper tabled by the British and Irish governments allowed the British government to renege on key commitments including the inquiry into the state-sponsored murder of Pat Finucane and an Irish Language Act,” he said.

Mr McGuinness said the Irish Government had also “abandoned the demand for full disclosure on the Dublin/Monaghan bombings and an inquiry into the massacre of civilians in Ballymurphy by the British government”.

“I am proud to be part of the Sinn Féin team seeking to reach agreement however this task is made all the more difficult due to the failures of the current Irish government.”