Home Secretary Theresa May, the front-runner who campaigned for a “Remain” vote in the June 23 referendum, said Britain needed to be clear about its negotiating stance and she would not be rushed into triggering the article this year.

Junior Energy Minister Andrea Leadsom, who has emerged in the early days of the contest as May’s strongest rival from the “Leave” camp, struck a more urgent tone, saying Britain needed to “get a grip and make progress”.

Britons voted by 52 to 48% to leave the bloc it had joined in 1973 and Prime Minister David Cameron said the next morning he would resign over his failure to keep the country in.

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Adding to the political turbulence, the vast majority of the main opposition Labour Party’s lawmakers openly denounced leader Jeremy Corbyn as unfit for the job but he has refused to resign, citing grassroots support.

Five candidates are vying to succeed Cameron as Conservative Party leader and prime minister, and the field will be whittled down to two by the party’s lawmakers over the summer, before grassroots party members pick the winner by Sept. 9.

Media reports on Sunday suggested that some Conservative lawmakers who back May were trying to persuade Leadsom and other candidates to stand down so that May could be quickly installed in Downing Street to bring back stability and make quicker progress towards negotiating the terms of Brexit.

But asked about this in an interview on ITV, May said she would not favor the so-called “coronation” scenario.

“I think there should be a contest. I think it’s important that members have their opportunity to have their say and I think that what people want to hear is what the arguments are and people putting those arguments together,” she said.

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EU leaders have been putting pressure on Britain to trigger article 50 quickly to avoid a prolonged period of uncertainty that is also destabilizing for the other 27 member states.

“We’ve got to be clear about what our negotiating stance is before we trigger that article 50, because once we trigger it then all the processes start,” said May.

Once the article is invoked, the clock starts ticking for a deal on the terms of Brexit to be agreed within two years.

“What is important is that we do this in the right timescale and we do it to get the right deal for the UK,” said May.

But Leadsom, who was one of the most passionate advocates of Brexit during the referendum campaign, said she would invoke the article as quickly as possible.

“We need to get on with it, we need to seize the opportunity,” she told BBC television.

“It’s about giving certainty to businesses, it’s about saying to the world ‘we’re open for business’. Let’s start getting some free trade agreements started as soon as we can. We need to get on with it, we need to get a grip and make progress.”

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On the subject of immigration, May appeared to distance herself from a long-standing Conservative goal to reduce immigration to tens of thousands annually from over 300,000 currently.

“We can bring immigration down to sustainable levels,” May said, adding that one of the strongest messages from the Brexit vote was a popular yearning for more control in this area.

“What I’ve also discovered over the last six years (as interior minister) is that this is somewhere where you’re constantly having to work at it, so you can’t just set a time period,” she said, adding that it was not all about numbers.

“There are factors you can’t always predict, what the timing and numbers…will be.”