Reality Check: Could Theresa May call an early election?

With the permission of the Queen, prime ministers used to be able to call a general election at a time of their choosing.

The introduction of the Fixed Term Parliaments Act, however, means that even if she wants to, Mrs May might not find it so easy.

The Act was introduced after the 2010 election to bind together the two parts of the new coalition government.

The discretion of prime ministers to pick the timing of elections was removed and the dates fixed five years apart - we are next due one on Thursday 7 May 2020.

The Act provides two mechanisms by which an early election could be triggered, which are:

• If two-thirds of MPs vote for a motion in favour of an early election (that is not two-thirds of those present, but two-thirds of all MPs - 434)

• If MPs pass a motion of no confidence in the government and an existing or new government cannot win a vote of confidence in the House of Commons within 14 days of the no confidence vote

Taking each in turn, the government does not have the numbers on its own to achieve a two-thirds majority so any vote would depend on what the other parties do.

Jeremy Corbyn has warned the Labour Party to prepare for an election next year and Newsnight reported in September that he planned to instruct his MPs to vote in favour of an early election if the government wanted to call one (although that has not been confirmed). Latest polls suggest that supporting an early election would be a mistake for Labour.

It is unlikely the Scottish National Party would come to the government's assistance in bringing about an early election.

Looking at the second mechanism, if other parties do not support an early election it would be unprecedented in British politics for a government to bring about its own downfall (though such engineering is not unknown elsewhere) and the government voting no confidence in itself could be a risky strategy.

More likely is that the Fixed Term Parliaments Act could be repealed or amended, to require, for example, a simple majority of MPs in favour of an early election, though the House of Lords may have something to say about this.

An amendment to existing legislation seems more straightforward than trying to reintroduce the prerogative power to call elections.

In short, the calling of an early election would require either a change in the law, or some unusual parliamentary gymnastics.