At the end of a day that began with reports of deadlocked negotiations, Theresa May has staggered across the line with a deal that gives her at least some hope of winning Tuesday's meaningful vote in the House of Commons. Conservative Brexiteers sounded sceptically non-committal as David Lidington, the prime minister's de facto deputy, outlined the terms May had agreed with Jean-Claude Juncker in Strasbourg.
DUP deputy leader Nigel Dodds reserved judgment until he had a chance to see the British government's unilateral declaration which was later published alongside the UK-EU joint interpretive instrument on the withdrawal agreement and the joint statement on the political declaration.
The joint instrument, which May stressed had the same legal status as the withdrawal agreement itself, gives legal force to the assurances offered by Donald Tusk and Jean-Claude Juncker in January on the temporary nature of the backstop. It says that if the EU drags its heels on negotiating a permanent trade agreement and appears to be seeking to make the Northern Ireland backstop permanent, Britain could trigger arbitration that could allow it to unilaterally suspend the backstop.
“Ultimately, the aggrieved party would have the right to enact a unilateral, proportionate suspension of its obligations under the withdrawal agreement … including the protocol. Such a suspension may remain in place unless and until the offending party has taken the necessary measures to comply with the ruling of the arbitration panel,” it says.
Backstop must be temporary
In its unilateral declaration, Britain says that its interpretation of the withdrawal agreement is that the backstop must be temporary and that if it is not possible to conclude a trade agreement which supersedes it, the backstop would no longer be temporary.
"If under these circumstances it proves not to be possible to negotiate a subsequent agreement … the United Kingdom records its understanding that nothing in the withdrawal agreement would prevent it from instigating measures that could ultimately lead to disapplication of obligations under the protocol … and under the proviso that the UK will uphold its obligations under the 1998 agreement in all its dimensions and under all circumstances and to avoid a hard border on the island of Ireland," it says.
This seeks to address the DUP’s central concern about the backstop: that it could become indefinite if Britain and the EU are unable to agree a trade deal. If it satisfies the DUP, most Conservative Brexiteers are likely to fall into line, giving the prime minister a fighting chance of confounding expectations and seizing a rare victory on Tuesday night.