[WATCH] Britain launches EU exit process

European Council President Donald Tusk has received the letter of notice from the British government, triggering Article 50 of the EU's Lisbon Treaty and marking the beginning of a two-year period in which the UK must form a new deal with the bloc.

Britain's permanent representative to the EU Tim Barrow hand-delivered the six-page letter to Tusk at 1:20pm to formally begin divorce proceedings.

UK Prime Minister Theresa described it “a historic moment from which there can be no turning back.”

“In accordance with the wishes of the people, the United Kingdom is leaving the European Union.”

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Delivering a statement in the House of Commons shortly after invoking Article 50, May said that leaving the EU presents the UK with a unique opportunity.

Britain would now make its own decisions and its own laws and "take control of the things that matter most to us - and we are going to take this opportunity to build a stronger, fairer Britain,” May said.

She pledged to "represent every person in the whole United Kingdom" during the negotiations - including EU nationals, whose status after Brexit has yet to be settled.

"It is my fierce determination to get the right deal for every single person in this country," she said, confirming that the rights of EU nationals will be an early priority.

May said she wants to not just protect the rights of workers, but build on them.

She added that she will negotiate as one UK, taking account the interests of all regions.

"For, as we face the opportunities ahead of us on this momentous journey, our shared values, interests and ambitions can - and must - bring us together."

May said she respects the position taken by EU leaders, who have said that the UK cannot “cherry pick,” and stay in the single market without accepting free movement.

“There will be consequences to leaving,” she said.

The Prime Minister continued that at a time when the growth of global trade is slowing and protectionism is on the rise, "Europe has a responsibility to stand up for free trade in the interest of all our citizens".

“Failing to stand up for European values would be a costly mistake,” she said.

Speaking in Brussels, Tusk said that the EU regretted that the UK was leave, “but we are ready for the process that we now will have to follow.”

He said that Brexit has made the community of 27 "more determined and more united than before."

"I and the Commission have a strong mandate to protect the interests of the 27. There is nothing to win in this process, and I am talking about both sides. In essence, this is about damage control," Tusk said.

"And what we should stress today is that, as for now, nothing has changed: until the United Kingdom leaves the European Union, EU law will continue to apply to - and within - the UK," he added.

In a statement, the European Council said its goal is "an ordinary withdrawal", adding it will circulate draft guidelines for the EU's negotiating stance on Friday.

"For the European Union, the first step will now be the adoption of guidelines for the negotiations by the European Council. These guidelines will set out the overall positions and principles in light of which the Union, represented by the European Commission, will negotiate with the United Kingdom.”

"In these negotiations the Union will act as one and preserve its interests. Our first priority will be to minimise the uncertainty caused by the decision of the United Kingdom for our citizens, businesses and member states. Therefore, we will start by focusing on all key arrangements for an orderly withdrawal.”