I have just chaired a meeting of the cabinet, where we agreed that the government should call a general election, to be held on 8 June.

The breakneck speed reflects a narrow window of opportunity in Europe. Any later would eat into the precious negotiating time reserved for Brexit and risk exposing the contradictions in Britain’s position. Instead, the prime minister hopes to exploit the lull between invoking article 50 and the upcoming French elections to strengthen her hand before the trials ahead.

I want to explain the reasons for that decision.

In fact, there is no mention at all of one of the biggest reasons, which is Tory party strength in the polls and the chance to increase its majority. To spell this out might tempt fate and look opportunistic, but to not even hint at it risks looking disingenuous.

At this moment of enormous national significance there should be unity here in Westminster, but instead there is division. The country is coming together, but Westminster is not.

It is hard to square this vision of parliamentary opposition with the ease in which legislation enabling article 50 sailed through parliament. It is true that Labour opposition to a hard Brexit is getting louder, but May implies it stands against the referendum decision. Critics and fans of Corbyn alike would argue the opposite.

Our opponents believe that because the government’s majority is so small, our resolve will weaken and that they can force us to change course.

Mischievous minds may wonder which opponents she has in mind here. It was the threat of Tory rebellion that forced climbdowns over the budget and various procedural Brexit concessions. A larger majority would give May the strength to plot her own course between the two wings of her own party.

I have only recently and reluctantly come to this conclusion. Since I became prime minister I have said that there should be no election until 2020, but now I have concluded that the only way to guarantee certainty and stability for the years ahead is to hold this election.

Expect more verbal gymnastics of this sort in the next seven weeks. That she believes the only way to ensure stability is to dissolve her government suggests May is also braced for far harder Brexit negotiations than she has been prepared to acknowledge so far.

This is your moment to show you mean it, to show you are not opposing the government for the sake of it, to show that you do not treat politics as a game.

This is intended as both a trap and a taunt to opposition MPs. If Labour sticks to its support for Brexit, there will be little to choose between them on the one issue where May could be vulnerable. She is gambling that reversing that position now would backfire among voters who still believe in their referendum decision. Any threat from the Liberal Democrats remains limited so early into the Brexit process.

It will be a choice between strong and stable leadership in the national interest, with me as your prime minister, or weak and unstable coalition government.

Just to rub in how weak the official opposition party is, May is not even prepared to concede they could form a government of their own.