Prime Minister Boris Johnson will hail the “dawn of a new era” later, as the UK prepares to leave the European Union after 47 years.

In a speech to be shown at 22:00 GMT – an hour before the official departure time – he will say Brexit is “not an end but a beginning”.

Johnson’s speech will be optimistic and will be an attempt to heal the internal division caused by Brexit, a charge that he has been leading since 2016.

In his pre-recorded address from Downing Street Johnson will say: “This is the dawn of a new era in which we no longer accept that your life chances – your family’s life chances – should depend on which part of the country you grow up in.”

“This is the moment when we begin to unite and level up.”

Johnson will describe Brexit as “not an end but a beginning” and as “a moment of real national renewal and change”, before ushering in an 11 month transition period where nothing is expected to change.

Brexit was originally scheduled for 29 March last year but was repeatedly delayed when MPs rejected a previous withdrawal agreement reached by the EU and former Prime Minister Theresa May.