Theresa May will trigger the two-year Article 50 EU exit process on March 29.
Tim Barrow, Britain’s EU ambassador, informed the office of Donald Tusk, EU Council president, on Monday morning that the formal letter would be submitted to Brussels next Wednesday.
Downing St declined to say whether the letter would contain any detailed negotiating objectives. Mrs May will make a Commons statement on the same day.
Mr Tusk said the Council would respond “within 48 hours” but a detailed EU negotiating position is not expected to emerge until later in the spring.
David Davis, the UK’s Brexit secretary said:
The Government is clear in its aims: a deal that works for every nation and region of the UK and indeed for all of Europe – a new, positive partnership between the UK and our friends and allies in the European Union.
The pre-announcement of the timing of the Article 50 letter is partly aimed at preparing financial markets for the formal start of the Brexit process which will last at least two years.
Downing St has been anxious in recent months to counter the risk that major Brexit announcements are inevitably accompanied by falls in the value of the pound.
Sterling is trading at a three-week high against the dollar at $1.2410 this morning.