Britain's prime minister, Theresa May, says she intends to begin the formal process of leaving the European Union by March 2017.

Speaking to the BBC on Sunday, May said she would seek to begin the 2-year negotiation process required to leave the EU in "the first quarter of 2017".

The BBC's Rob Watson reports for NPR's newscast unit:

"It feels like a big moment. We now know Theresa May wants Britain to have left the EU by around April 2019."What's still somewhat less clear is what post-Brexit Britain will look like. Mrs. May told the BBC she wanted the right deal for British business in terms of trade in goods and services, but she also said the referendum showed the British people wanted control of the free movement of people from the EU So, the starting gun has effectively been fired in what Mrs. May herself described as the complex process of Britain's EU departure."

As NPR has reported, the first step toward leaving the EU is for the U.K. to formally notify the European Union of its decision to leave. This is done by invoking a provision known as Article 50 of the Lisbon Treaty. It's up to the prime minister to pull the trigger on Article 50 — which is what May has said she will do in early 2017.

(If you want to know a lot more about all the steps that need to happen for Britain to leave the EU, NPR's Jackie Northam has you covered.)

May also announced what she called a "great repeal bill" that will be introduced in parliament next year, and will remove the blanket European Communities Act from British law, and instead enshrine individual EU laws that Britain intends to keep.

In the interview Sunday with the BBC, May said the bill, which would take effect when the two-year exit process from the EU is complete, "means the UK will be an independent sovereign nation, it will be making its own laws."

Both May and the U.K.'s "Brexit" secretary, David Davis, are expected to address the bill and the exit timeline at the annual meeting of Britain's Conservative Party, which begins today.

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