Britain's ambassador to the EU, Tim Barrow, informed European Council President Donald Tusk on Monday about the date when the UK intends to invoke Article 50 of the EU Treaty, the mechanism for starting the Brexit process.
The United Kingdom held a referendum last June in which Britons voted by a 52-48 percent margin to leave the EU, the first member state ever to do so.
Brexit Minister David Davis said the withdrawal process will take Britain to "the threshold of the most important negotiation for this country for a generation."
"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," Davis added.
The notification of triggering Article 50 will come in the form of a letter delivered to Tusk next week, which will likely plunge Britain into a period of intense uncertainty.
Article 50 allows for two years of talks to decide an EU member state's separation terms, "taking account of the framework for its future relationship with the Union"
May has said she wants to make Brexit as painless as possible. But EU leaders, anxious to avoid encouraging others in the 28-member bloc to split, have said they will not give May an easy ride.
Although Britain as whole voted to leave the EU, Scotland and Northern Ireland voted to stay in the bloc.
The Brexit vote in June has prompted nationalists in Scotland and Northern Ireland to call for holding a referendum for independence from the United Kingdom.
Scotland’s First Minister Nicola Sturgeon wants her country to hold a referendum on Scottish independence immediately after Britain's exit from the EU.
The largest Irish nationalist party, Sinn Fein, has also called for a referendum on splitting from the United Kingdom and uniting with the Republic of Ireland "as soon as possible."