Theresa May will trigger the two year process of leaving the European Union on March 29, No 10 has announced.
Sir Tim Barrow, the UK’s ambassador to the EU, formally notified the office of Donald Tusk, the EU Council president, with a letter on Monday morning.
On Wednesday next week Mrs May will formally notify Mr Tusk by writing him a letter and then giving a statement to MPs later in Parliament.
The Prime Minister’s official spokesman said: “There will be a letter. We have always been clear we would trigger by the end of March and we have met that timetable.”