UK Prime Minister Theresa May has signed the letter that will formally begin the UK’s departure from the European Union.
The UK voted to withdraw from the EU in a hotly contested and controversial referendum last June.
The UK’s permanent representative to the EU, delivers a letter of notification to European Council President Donald Tusk.
At the same time across the channel in London, May will stand to deliver a statement to the house of commons, confirming that the brexit process has begun.
Formal notification will start the clock ticking on two years of talks between the UK and the EU to conclude the terms of Britain’s exit, and establish future relations between the two parties.
The presidents of the European Parliament and the European Commission, Antonio Tajani and Jean-Claude Juncker and German Chancellor Angela Merkel may address brexit later.