Brexit Minister David Davis (L) and EU's  chief Brexit negotiator Michel Barnier

In a speech delivered in September in Florence, Italy, May formally requested the implementation period of two years to cushion Britain’s exit from the EU in March 2019. The EU’s 27 remaining members have not yet formally discussed the terms of a transition period.

Brexit Minister David Davis said on Wednesday that Britain wants an outline agreement with the EU by the end of March. Davis appeared to suggest that the British parliament may not get a vote on the final Brexit deal until after Britain has left the European Union.