It is now a distinct possibility that Theresa May will fail to rally a parliamentary majority.

Faltering Negotiations

DUP sources on Tuesday signaled that negotiations over a workable parliamentary majority that will support Mrs. May’s government are faltering.

The Press Association says the DUP is warning that its parliamentary support “can’t be taken for granted,” telling the BBC that the government should give “greater focus” to the negotiations. A deal is “certainly not imminent,” the Irish Times report.

The Conservatives and the DUP have been negotiating for 11 days, apparently without promising results. But Conservative Party sources told the BBC that a last minute deal is still possible.

On Wednesday, the Queen was expected to deliver a speech marking the beginning of the new government’s work and its legislative priorities. The DUP leader, Arlene Foster, signaled that the DUP will support Theresa May’s government in the vote of confidence following the speech, but that means little in the medium to long term.

Mrs. May cannot count on a solid parliamentary majority over the next two years, unless she looks for an ally elsewhere, probably at the expense of a so-called “hard Brexit.”

Electoral mathematics

That would mean the UK may go back to the polls, or she would be forced to form a minority government.

On June 8, the Conservatives got 318 seats in a 650 seat parliament. The magic number for a majority government is, in theory, 326 seats. However, Sinn Fein in Northern Ireland did better than any previous election, taking seven seats. As the Irish Republicans will not take an oath to the Queen and will leave their seats vacant, the threshold for the governing majority falls to 323. That means the Conservatives are six MPs short of a majority. Until Tuesday evening, the assumption was they would be able to count on the DUP’s 10 seats. That is no longer certain.

Political cleavages

The DUP is demanding a guarantee that pensions will continue to rise to meet a surge in inflation and there will be no tax rises. And although the unionists are supportive of Brexit, they want guarantees of freedom of movement and an open border with the Republic.

Meanwhile, the DUP is a political liability for the role of the British government as an arbiter of the Good Friday agreement. While the Irish Prime Minister, Leo Varadkar, extended his political support to Theresa May on Monday, suggesting that a deal with the DUP does not necessarily undermine the role of the British government, that is not the position of Sinn Fein.

Sinn Fein is calling for a “unity poll” – referred to in the Good Friday Agreement as a “border poll” – in the event of a hard Brexit. Last week, Gerry Adams made clear he considers that a government that would include the DUP would be in breach of the Good Friday Agreement. As Sinn Fein is a necessary player in North Irish politics, it will be hard to proceed without their consent, especially since the collapse of the power-sharing government in Belfast in January.