Ireland's Taoiseach, Leo Varadkar | Carl Court/Getty Images Dublin’s 5 Brexit demands show path to sufficient progress Following an enhanced offer from the UK on its financial settlement, the Irish border issue is now the subject of intense negotiations.

LONDON — The Irish government is pressing for five written commitments from Theresa May that would clear a path to phase two of Brexit talks.

With just five days until the U.K. prime minister meets Commission President Jean-Claude Juncker to present the U.K.'s renewed offer over lunch in Brussels, the Ireland issue is the subject of intense negotiations.

The U.K. has signaled it is prepared to dramatically widen the scope of its financial offer to the EU and with both sides believing that the issue of citizens’ rights is close to agreement, the Irish situation has emerged as the biggest obstacle to “sufficient progress” being granted at a summit of EU leaders in Brussels in mid-December.

One senior diplomat said the chances of a breakthrough on Ireland were “60/40" in favor of a deal before the summit.

However, the diplomat cautioned that a deal was unlikely to be struck in time for it to be presented when May and Juncker meet next week. A second negotiator closely involved in the talks warned that Britain was still some way off meeting the criteria that the EU has put forward on behalf of Ireland and the rest of the EU27.

Irish Prime Minister Leo Varadkar last week publicly threatened to block the move to phase two of the talks unless the U.K. adequately addresses Ireland's concerns about the reimposition of a hard border with Northern Ireland. So far, the rest of the EU27 have been resolute in their support for Ireland, citing its "unique" position with respect to Brexit.

“This is a can that cannot be kicked down the road," a senior EU diplomat said, noting that sufficient progress now hinges on the Ireland question. "We cannot accept a kind of a check-in-the-post approach to this.”

Britain has vowed not to introduce any physical infrastructure on the border with the Republic, but has argued that the issue cannot be fully resolved until a U.K.-EU trade and customs agreement is hammered out in the second phase of the talks.

Dublin has made it clear, however, that it is not willing to give the go-ahead to phase two on the promise that it will be dealt with later — a position also adopted by EU negotiator Michel Barnier.

“It has to be more than simply scribbling a signature at the bottom of the page saying we can sign on to the principles," the senior EU diplomat said. "It’s how you implement, protect and sustain the principles, that’s what’s required.”

The Irish government wants clear, early recognition from British negotiators that not all of its concerns are likely to be solvable in phase two of the Brexit talks and that unless the U.K. can offer “specific solutions” to the border issue (which Dublin maintains is not possible) the EU negotiators will not accept that "sufficient progress" has been made in the divorce talks.

Dublin's red lines

With the deadline fast approaching, the Irish government has put five diplomatic demands on the table, according to two European diplomats familiar with the negotiations.

“We’re not going to be overly prescriptive on the wording," the senior EU diplomat said. "We’re interested in the outcome, but they are going to have to give clear commitments that will guarantee clear courses of action."

The first commitment demanded by the Irish is a written assurance that there will not be regulatory divergence “in EU-related matters such as to require a hard border,” according to one EU27 diplomatic official involved in the talks.

In London, such requests are viewed as tantamount to demanding Northern Ireland remains in the EU's single market — a clear breach of the U.K. government's red lines. Privately, EU officials insist this is not the case but are clear that the U.K. must offer some way around what Brussels views as London's contradictory positions: leaving the single market; avoiding a hard border between Ireland and Northern Ireland; and refusing any regulatory or other barriers between Northern Ireland and the rest of the U.K.

The second — closely linked — red line for Dublin is that there is a written commitment to avoid "customs complications" and "customs divergence" between Northern Ireland and Ireland. While again stopping short of demanding Northern Ireland remains in the customs union, such a commitment would likely bind the British government into the closest possible U.K.-EU customs agreement post Brexit, potentially constraining its ability to negotiate free trade agreements with third countries.

A third commitment sought by Dublin is for the U.K. to guarantee nothing is done which might damage the Good Friday agreement. The Irish government is looking for a form of words in which London pledges to "implement, protect and sustain the principles" of the 1998 treaty, and some Irish officials say there are already worrying signs that Britain does not fully appreciate the risks Brexit poses to the peace deal.

Fourth, Dublin wants a binding commitment to maintain the common travel area between the U.K. and Ireland, which Dublin believes has already been "more or less agreed."

The Irish government's fifth demand is that it wants a guarantee that discussions over specific border issues will continue after phase one and not just be subsumed into the U.K.-EU talks on the future relationship.

The EU27 diplomatic official, who spoke to POLITICO on condition of anonymity, said both sides wanted to tie everything up seven days before the European Council meets in Brussels. This gives Theresa May until the end of next week to meet the Irish demands or risk sufficient progress being blocked when EU leaders meet on December 14, exploding the Brexit process and thereby increasing the chances of a disorderly divorce.

Speaking to journalists en route to a visit to Jordan, May said: "We’ve been very clear as we and the Irish government both want to ensure that there is no hard border there. I think there are a number of ways in which that can be achieved and we’re talking with the Irish government and continue to do so."

The chances of a deal being struck by Monday when May meets Juncker remain slim though.

“A compromise will have to be found,” the official said. “We’re looking for language which does not tie either side down to anything which will be unacceptable.”

Not everyone is convinced, and while the EU27 are negotiating as a bloc, Dublin is viewed as first-among-equals in determining if there is sufficient progress on Irish matters.

"Nobody thinks the Irish question will be solved before the European Council in December. It is up to Ireland to assess whether there is sufficient progress, and what the U.K will accept, we don’t know yet,” another senior EU diplomat said.

In public, Varadkar and Irish Foreign Minister Simon Coveney have warned that Ireland will not simply fall into line because of its interest in eventually agreeing an overall EU-U.K. trade deal. They have called for Northern Ireland to be given special dispensation to remain within the EU customs union to solve the problem, a position London seems to reject outright.

Under the British proposal, 80 percent of cross border trade by small and medium-sized companies would be exempt from any customs controls. The remaining 20 percent would not face checks on the border but would be required to declare imports and exports at intervals during the year.

At its heart, Dublin believes a hard border is unavoidable if Northern Irish regulatory standards diverge from the EU along with the rest of the U.K. after Brexit. Still, some officials have suggested it is possible to find a compromise in time for the summit next month.

Speaking in Brussels Wednesday, Irish European Commissioner Phil Hogan said: “In the same way we have seen movement in the last 24 hours in relation to the financial settlement, I expect we will see movement [on Ireland] as well. And hopefully we will. Because nobody wants to see a situation arise when we have to, again in December, declare insufficient progress in order to allow the next phase.

"I am sure that our friends in the United Kingdom are quite concerned about that, and they understand what they have to do,” he added.

Quentin Ariès, Jack Blanchard and Maïa de La Baume contributed reporting.