London CNN  — 

Britain’s exit from the European Union moved another step closer Thursday after the legislation enabling the country’s departure was given royal assent by Queen Elizabeth II.

The Queen’s signature means that British Prime Minister Theresa May is now able to move forward and trigger Article 50, allowing formal talks to begin between Downing Street and the EU’s 27 member states on the terms of the divorce.

The negotiations are expected to take up to two years once May finally invokes the leaving mechanism later this month.

What is royal assent?

The news of the royal assent was announced in the House of Commons by the Speaker of the House.

After a bill passes both the House of Commons and House of Lords, it requires royal assent to become law.

That means that the head of the British monarchy must sign the bill before it becomes an Act of Parliament.

Such a process has become a formality in modern times. The last time royal assent was refused was by Queen Anne in 1707.

What happens next?

The announcement means May remains on course to invoke Article 50 before the end of March.

However, on Wednesday Brexit Secretary David Davis admitted that the British government had not yet carried out an assessment of what leaving the EU without a deal would have on the economy.

When asked at a parliamentary committee hearing whether an assessment had been carried out, Davis said: “If you mean under my time, no.”

Davis also suggested that claims that a “no deal” scenario “is not as frightening as some people think” but said he would be able to give a more accurate forecast in a year’s time.

There was also a warning from a top European official that Britain should stop threatening the EU ahead of the Brexit negotiations.

Donald Tusk, President of the European Council, said the EU would not be “intimidated” by threats from Britain that it would prefer to walk away from Brexit talks if it did not get its way.