LONDON, March 28 (Xinhua) -- British Prime Minister Theresa May on Tuesday signed the Article 50 notification letter which will officially begin Britain's exit from the European Union (EU), local media said.

Nine months after the divisive Brexit referendum last June, May will officially trigger Article 50 in the letter that will be hand delivered on Wednesday to European Council President Donald Tusk.

At the same time, in a statement to MPs in the Commons, she will pledge to get the right deal for everyone in Britain, including EU nationals living in this country, according to a Sky TV report.

"We are one great union of people and nations with a proud history and a bright future," she will say. "And, now that the decision has been made to leave the EU, it is time to come together."

By triggering Article 50 of the Lisbon Treaty, the Britain and EU is expected to have a two-year process in which the terms of exit will be negotiated. Unless both sides agree to extend the deadline for talks, Britain will leave on March 2019.

Article 50 refers to the formal procedure by which an EU member state notifies the European Council that it intends to leave the bloc.