On Friday 8 December, the Taoiseach told the Irish people that the backstop agreement was "rock solid and cast iron" and that his Government "protected what it sought to protect and achieved what it sought to achieve". Paragraph 46 of the December joint report states the agreement is "made and must be upheld in all circumstances, irrespective of the nature of any future agreement between the European Union and United Kingdom."

Paragraph 49 states that while it is Britain's intention to achieve these objectives through an overall relationship with the EU, which every Member will support, the UK will propose "specific solutions to address the unique circumstances of the island of Ireland" - or a backstop - should this not be possible. If there was no agreement between Britain and the European Union on trade, there is some certainty for businesses on either side of the Border and for the people in Ireland that there would be as much alignment as possible with the rules of the customs union and Single Market.

The Taoiseach's cast-iron guarantee is in tatters. A paper was published by the British Government a couple of days ago which essentially took the backstop off the table and turned it into a UK-wide extension of the implementation period. It is time-limited, and as Mr. Michel Barnier said, "Backstop means backstop". We have an extraordinary situation where we had something on the table that was a real and tangible political agreement, but that has been turned into something entirely different because of internal wrangling in the Tory party. We have to hold the Taoiseach to account, and the best way to do so is on the promises he makes and the benchmarks he sets. He said this was cast iron. How could he say that if there is still wrangling over what it all means, and the British Government has come back with proposals which essentially take it off the table?

The Taoiseach also said that he wanted to see real and substantial progress by June.

Nobody could argue with a straight face that we have seen real and substantial progress. In fact, it is quite the opposite because we have gone backwards. However, the Taoiseach is prepared to allow the farce to continue whereby the Irish issues are now in the melting pot in what will be very tough negotiations when the real pressure comes on in October. That is not what we were told; it is not what we were promised. The Taoiseach knows my party wants the Government to succeed on this issue because we all want the best for Ireland. We are in a very difficult place, however. What will be the Government's approach at the June summit? Will the Taoiseach hold firm to the commitment he made and will he ensure that there will not be any moving on from these issues until we get the real and substantial progress we were promised?

Yes, we will hold firm to the commitments we made and we expect the United Kingdom Government and others to hold firm to the commitments they made. In December, a political agreement between the United Kingdom and the European Union that gives us a number of guarantees and assurances - for example, on the common travel area, for ongoing PEACE funding for Northern Ireland and Border areas and with regard to citizens' rights - was reached. I do not think anyone is doubting these at present. They are all very much cast-iron guaranteed. I also used the term "bulletproof" regarding commitments on the Border. In addition, I said it was the end of the beginning and not the beginning of the end, that we needed to be vigilant and that we had to insist that the guarantees we were given were written into the withdrawal agreement. That is where matters stand.

In March, the European Union - all 27 member states together backed by the EU institutions - produced a draft text of the withdrawal agreement, including a protocol on Northern Ireland and Ireland, that put in legal form everything we achieved and secured in December. Last week, the United Kingdom Government produced a paper which represents a small step in the right direction but which I do not believe to be adequate. It is at very best a partial solution to part of the problem. It deals with customs, which is welcome, but not with regulatory alignment, which is essential to avoiding a hard border. In many cases, perhaps not all, regulatory alignment will be required. Even though it is not in the written text of the UK's amendment, it seems to imply that there would be an expiry date sometime in 2021. This is not something we can accept. The whole point of a backstop is that it implies it will exist unless and until there is a new treaty between the EU and the UK that makes it unnecessary. That is where we need further movement and concessions from the UK Government between now and the forthcoming summit. If we do not get it then, quite frankly, nobody will be able to say that sufficient progress has been made. We will need to intensify the negotiations in the months ahead to ensure that happens. What the European Union is very firm on is that we are not going to be in a position to discuss long-term issues, such as the new trading relationship and the new arrangements that will exist between the UK and EU, until such time as the withdrawal agreement and the backstop are agreed.

The problem is that we have no legal framework. That is the issue. We said in December that this is simply a political agreement - and, yes, that is important and substantial - and we welcomed the progress that was made. However, we were also wise and advised the Taoiseach not oversell the agreement and to work on getting the legal clarity and framework that would provide certainty. The reality is - I think this is genuinely lost on the Taoiseach - that the British Government has essentially taken the cast-iron guarantee off the table. In the paper it has written the British Government has restructured matters in order to write the North out of the script and turn what is a backstop or permanent solution in the event of no deal into an extension of the negotiating period. What will happen in the event that there is no deal? What will happen then for Ireland? The paper published by the British Government does not say that, it says it is time-limited. This is a real problem. We have to hold Taoiseach to account and the way to do so in the context of this issue is to encourage him to hold the British Government to account and to ensure that the latter does not resile on commitments it gave in December. The Taoiseach and his European Union counterparts do this at the forthcoming summit. While the Taoiseach says that this will happen, what real and substantial progress needs to be made - separate from what is in the paper published by the British Government - between now and the summit for him to be able to say that real and sufficient progress has been made?

My priority is to secure the agreement and not to sell it. We secured a political agreement in December and we will secure a legal withdrawal agreement by October. That is exactly what I am focused on and what the Tánaiste and all of our teams are focused on also. That is what we intend to do.

We need to bear in mind that dealing with Brexit is not solely a matter of considering North-South issues and Northern Ireland issues. They are of paramount importance because they are issues of national interest, but the east-west element is also important. If someone is a farmer, involved in the agrifood sector or involved in tourism, a small Irish SME that exports to the UK or a big multinational company exporting to the UK, actually having the latter in a customs arrangement or customs partnership with the European Union is to our advantage. That must be borne in mind. If the UK can produce solutions that allow us to avoid a hard border, not just North and South but also east-west, that is positive.