However, ahead of that all-important summit, the so-called "Sherpas" — named after mountain guides, typically from Nepal — will meet to design the template for the talks, which is a huge task, given the conflicting interests of both the UK and the remaining 27 member states.
The first issue will be the timescale of the talks. Under Article 50 of the Treaty of Lisbon — whose author, the British diplomat Lord Kerr of Kinlochard never had a Brexit in mind when drafting the text in the event of a military coup in one of the EU states — the talks can last a maximum of two years.
UK Govt's 'plans' for #Brexit high risk for Wales say @Demos #Cardiff Central also has high risk loss of EU workers https://t.co/BrFj5kN1UX pic.twitter.com/AFaRLOS7Ka
— Jo Stevens MP (@JoStevensLabour) 11 April 2017
In reality, the timescale is much shorter than that, given the French presidential and German federal elections are yet to take place and little will happen until the outcome of both is known. France goes to the polls in April and May, while Germany will wait until September.
Then there is the battle over priorities. In her letter to Tusk, May wrote: "The United Kingdom wants to agree with the European Union a deep and special partnership that takes in both economic and security cooperation. To achieve this, we believe it is necessary to agree the terms of our future partnership alongside those of our withdrawal from the EU."
There are now sherpas involved in Brexit. Are we climbing the mountain of conflict?
— (((StephenDaisley))) (@JournoStephen) April 5, 2017
Thus, she is seeking to negotiate both Britain's withdrawal from the EU and its new trade relationship with the EU 27 post-Brexit at the same time. However, the EU's original position was that Britain must first "divorce" the EU and then — and only then — begin talks on a new trade agreement.
"The negotiations must first clarify how we will disentangle our interlinked relationship. Only when this question is dealt with can we — hopefully, soon after — begin talking about our future relationship," German Chancellor Angela Merkel told reporters.
Citizens' Rights
In his guidelines set out to EU leaders following the Brexit announcement, Tusk wrote: "The United Kingdom's decision to leave the Union creates significant uncertainties that have the potential to cause disruption, in particular in the UK but also in other Member States."
"Citizens who have built their lives on the basis of rights flowing from the British membership of the EU face the prospect of losing those rights. Businesses and other stakeholders will lose the predictability and certainty that come with EU law."
Meeting PM May to make sure Brexit talks get off to good start. Agreed to stay in regular contact throughout process https://t.co/udh7VEsoHy
— Donald Tusk (@eucopresident) 6 April 2017
The word "phased" shows a slight softening of the EU's stance with the door held open for so-called parallel talks — both divorce and trade deal — running concurrently, one slightly ahead of the other.
Two issues will be settled early: the rights of EU citizens in the UK — as well as UK citizens living in other EU states — and Britain's 'leaving fee." On both counts, the Sherpas meeting in Brussels appears to be aligned.
May wrote: "There are, for example, many citizens of the remaining member states living in the United Kingdom, and UK citizens living elsewhere in the European Union, and we should aim to strike an early agreement about their rights."
On the "divorce" bill, she said: "We will need to discuss how we determine a fair settlement of the UK's rights and obligations as a departing member state."
If those two points are agreed early — even in the months before the German elections — then the chances of a trade deal being reached before the end of the two-year deadline look more likely, although it is hard to see how a new trade deal outside of the single market area — with all the obligations that brings — will be anything other than an uphill struggle. Britain will need all the Sherpas it can find.
