Sir Tim Barrow to hand-deliver article 50 letter to Donald Tusk

Sir Tim Barrow, the UK’s permanent representative in Brussels , is to personally hand over a letter from the British government to the European council president, Donald Tusk, to provide notification of Britain’s intention to leave the European Union.

Once the letter is received by the European council, the clock will begin ticking on two years of talks regarding the terms of withdrawal allowed under article 50 of the Lisbon treaty.

Barrow, who was political director at the Foreign Office in London before moving to Brussels, replaced Sir Ivan Rogers as head of UKRep in January. Rogers had resigned in frustration, urging fellow civil servants to continue to provide impartial advice, and stand up to “ill-founded arguments and muddled thinking”.

At the time, a No 10 spokesperson called Barrow “a seasoned and tough negotiator, with extensive experience of securing UK objectives in Brussels”.

In a bullish appearance in front of the Commons EU scrutiny committee earlier this month, Barrow insisted the UK could strike a free-trade deal with the EU within two years – something the European commission has suggested is not possible.

Tusk is expected to make a short statement acknowledging receipt of the letter on Wednesday. On Thursday he will circulate among the remaining 27 member states a draft copy of the EU’s negotiating guidelines, which will provide a broad response to the British government’s letter.

Those guidelines will not be formally adopted by the EU27 until a special summit on 29 April in Brussels. The European commission will issue more detailed directives on the EU’s negotiating stance shortly afterwards but these will need to be adopted by a meeting of EU27 ministers in May, before negotiations with the UK can finally begin.