Since the Stormont House Agreement was reached at Christmas, Sinn Féin has been engaging positively in party leaders' meetings at Stormont to ensure its full implementation.

However, it became clear last week that the DUP was intent on reneging on commitments in that agreement. Martin McGuinness discovered that it was the intention of the DUP to provide only partial protection to current recipients of benefits and no protection whatsoever for future recipients contrary to the Stormont House Agreement. In our view, it intended concealing this until after the welfare reform legislation was passed.

I am sure the Taoiseach will agree that this is not part of the Stormont House Agreement. As a result, Sinn Féin and the SDLP had no option but to prevent the Welfare Reform Bill going through the Assembly. Martin McGuinness has made it clear that it is our focus to resolve these problems. Our record has been very consistent. The late Ian Paisley said that Sinn Féin kept every promise it made. Despite refusals to honour the Good Friday Agreement and subsequent agreements, including the absence of Acht na Gaeilge, a bill of rights, a civic forum and an inquiry into the murder of Pat Finucane, Sinn Féin has not given up on the process and we will not give up on the process.

It is clear, however, that political institutions must deliver for citizens, particularly disadvantaged citizens and those with disabilities. That is more important than other considerations. Does the Taoiseach agree that a resolution to the current difficulties will only be found by everyone adhering fully to the terms of the Stormont House Agreement?

I certainly agree that this is a serious matter and that, prior to Christmas, the discussion was about whether the institutions would survive. The opportunity for both Governments to become involved as co-guarantors of the Good Friday Agreement together with the dedicated work of the Minister for Foreign Affairs, the Minister of State at the Department of Foreign Affairs and Trade, Deputy Sherlock, the First Minister, the Deputy First Minister and the parties brought about the Stormont House Agreement.

I am interested to hear Deputy Adams say that the Deputy First Minister discovered that the DUP was not going to implement the agreement that was arrived at. It should also be noted that the Minister and Minister of State from this Government were not party to the detailed discussions about welfare reform that were an element of the agreement being arrived at. I am not sure how the Deputy First Minister discovered that the DUP intended to renege on the agreement if this is the case. Was it through a memorandum, comment or paper provided by the DUP saying that it intended to renege on the agreement?

With the British general election taking place early in May, there is an opportunity to work this out as mature politicians. The essence of politics is called into being here. This can only be dealt with by the First Minister and the Deputy First Minister who must explain to the other parties what this row is about. I would like to find out the nature of the discovery that the Deputy First Minister was able to make. How was he able to discover that the DUP suddenly intended at a certain point to renege on an agreement entered into in December? I agree with the Deputy that this should not have happened and can be rectified. It can only be rectified by the politicians hammering out what it is they agreed upon and being very clear about it in the interest of the people of Northern Ireland.

I am disappointed that the Taoiseach does not know how Martin McGuinness discovered it because the Taoiseach's officials were fully briefed on that over the weekend, so he should know. Martin McGuinness discovered it because we were given papers - we believe by mistake. When he discovered this, he spent several days last week, including during our Ard-Fheis, trying to meet the DUP. The DUP failed to engage with us but it was fully informed about our concerns. These are red line issues because the essence of mature politics must be protecting the disadvantaged - those who need the protection of society. That is the core of this agreement.

The Taoiseach may recall that in 1998, just after the signing of the Good Friday Agreement, Senator George Mitchell said that this was the easy bit and that the hard bit was implementing it. That has been our experience. I have been critical at times of the Government's handling of Northern Ireland issues but at the same time, I know that they are very challenging and require a constant focus with the British Government on the ongoing process to ensure in particular the need for everyone to fulfil commitments. In the absence of such clarity, every effort must be made to ensure all agreements are faithfully implemented. Does the Taoiseach agree that the resolution of the current difficulties will be only be found by everyone adhering fully to the terms of the Stormont House Agreement?

The Stormont House Agreement means particular conditions being adhered to. I do not have in front of me the difference between the detailed discussions on welfare reform conducted before Christmas before the agreement was arrived at and the details that apply now for welfare reform since the agreement was put together. There seems to be a discrepancy somewhere in the mathematics if this is what the row is about. Obviously, the Government was not party to the detailed discussions prior to Christmas about what welfare reform would mean for people but there seems to be a change in the figures that apply. I think one must go back to that point - what was laid out in detail in papers before Christmas and what has brought about a change in those figures that affect people with social welfare payments in various forms in Northern Ireland.

This is a very serious political matter. These institutions have paved the way for many years since the Good Friday Agreement. It has not been an easy journey in many respects. This row was brewing before Christmas. All of the parties and the two Governments got involved and agreement was reached on a set of figures with details about them. The agreement was signed off, accepted and welcomed by everybody. There now seems to be a difference in those figures. What has happened? I think the Deputy First Minister needs to go back and discover why this drift in these figures occurred, if it happened.

He knows.

If they were set out before Christmas and signed off, accepted, commented on and welcomed by the Deputy First Minister, more fulsomely than by Deputy Adams, what has happened that the figures are now different from those he accepted and agreed to before Christmas? The political discussion must deal with that. We do not want a situation where the parties walk away when it comes to the first difficult decision. They welcomed this before Christmas and signed off on those conditions. They must go back to where that welcome applied in the first instance.