Once British Prime Minister Theresa May officially triggers the Brexit, the initial negotiation process is expected to be slow. May's spokesman has said she will invoke Article 50 of the European Union treaty on March 29 by sending a letter to European Council President Donald Tusk, in keeping with the British government's self-imposed deadline. That will start the clock on a two-year negotiation process over the terms of the United Kingdom's departure from the Continental bloc.
But some formalities will have to be observed before the negotiations can begin. Tusk will reply to the United Kingdom's letter with some draft guidelines for the negotiations within 48 hours of receiving it. EU leaders will then hold an extraordinary summit, expected to be scheduled sometime in April. At that meeting, the leaders will begin sketching out the framework for Brexit negotiations. A framework will be agreed on and then sent to the European Commission, which will prepare more detailed guidelines for the discussions, to be approved by member states on the EU Council. Technically, only a qualified majority of the council would need to approve the guidelines, though member states typically strive for consensus over important decisions such as this one.
Once the directives are approved, the commission will hold a mandate to negotiate for the European Union and will then issue a recommendation to open the talks. Only after member states have authorized the recommendation can the United Kingdom and European Union enter discussions over the Brexit. Because the whole process could last several weeks, negotiations are not expected to start until May at the earliest and may not begin until July.