Ever since Theresa May became prime minister, after Britain voted to leave the EU on June 23 and David Cameron resigned, the possibility of an early election has hovered in the background. May has strenuously denied that this was her plan.

In September, she said: "I'm not going to be calling a snap election. I've been very clear that I think we need that period of time, that stability, to be able to deal with the issues that the country is facing and have that election in 2020." As late as last month, Downing Street was denying that an early election was on the cards.

So what has changed? Over the past few months, May has set out her vision for a hard Brexit in which Britain does not retain any kind of partial membership of the EU. In Tuesday's statement announcing an election on June 8, May made it explicit that she is seeking to strengthen her mandate for this, saying that "at this moment of enormous national significance here in Britain, there should be unity in Westminster."

The numbers suggest that May is likely to significantly increase her currently small majority with a snap election. The Labour Party is in a dire state, riven by internal conflict and dominated by criticism of leader Jeremy Corbyn. An average of all opinion polls current has the Conservatives on 42 percent and Labour on 27 percent, enough to deliver a substantial majority to May.

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"The Labour Party is at sixes and sevens on its stance on Brexit," said John Curtice, professor of politics at the University of Strathclyde. "There are divisions inside the Conservative Party, but the opposition is probably even more divided on the subject and she's probably banking that so long as this remains the central issue, the Labour Party will not be capable of fighting an effective alternative position."

A cynical move?

Some voters applauded the move. "This is a brilliant tactic on the part of the prime minister," said Matthew Brooke, a Leeds-based engineer who backed Brexit. "Labour offers no credible opposition. All the Brexit supporters - many of whom are also Labour voters, to be fair - will get out to vote and show their approval."

The Brexit referendum in June exposed deep divisions amongst the British public, and there is some concern that the election will effectively be a rerun of the referendum.

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"This is a cynical move by May, who clearly wants to increase her majority so she can force through a hard, economically catastrophic Brexit unopposed, or as close to unopposed as possible," said Zoe Lawrence, a London-based charity worker. "She talks about the national interest but I can't see that this is in anyone's interest but the Conservative Party's. How can we possibly justify the expense and upheaval of another vote so soon after the referendum?"

Most agree that the election is likely to be a platform for continued divisive debates about immigration and the future of the union.

"We are facing a political crisis in Northern Ireland which has been largely ignored by politicians in Westminster, and a renewed call for Scottish independence," said Peter Franklin, a Belfast-based writer. "It seems frankly irresponsible to hold an election in this context - whatever happened to the need for stability?"

Taking a gamble

Of course, as with any election, May is taking a gamble. Although Labour's position in the polls is terrible, many of the party's MPs are in safe seats that are highly unlikely to vote Conservative. It is also worth noting that opinion about Brexit remains divided amongst Conservative voters.

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"We should bear in mind that Theresa May is very much going for a 'vote Conservative for my vision of Brexit,' and that perhaps is going to make some Conservative voters unhappy," said Curtice. "If that lead were to narrow then we could discover she is back with a rather smaller majority than perhaps she is hoping for."

The Liberal Democrats, who currently have only eight MPs, have fought several by-elections on an anti-Brexit platform, pledging to hold a second referendum. The party leader, Tim Farron, immediately issued a statement positing the Liberal Democrats as the anti-Brexit option: "If you want to avoid a disastrous hard Brexit. If you want to keep Britain in the single market. If you want a Britain that is open, tolerant and united, this is your chance."

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Some pro-Remain voters see the latest development as an opportunity.

"Perhaps we can swing some seats towards candidates who are fully committed to remaining in the EU," said Aisha Hazaria, an Edinburgh-based administrator. "Of course we won't win, but there is an opportunity here to re-open the debate and change the tone of Parliament's response to what I have no doubt will become increasingly desperate Brexit negotiations. I'd like to see cross-party alliances to this end. I'll be campaigning for pro-Remain candidates regardless of their party."