British Prime Minister Boris Johnson has lost his working majority after a Tory MP defected to the Liberal Democrats.

Conservative MP Phillip Lee crossed the floor of the House of Commons and joined the Lib Dem benches just as Mr Johnson began giving a statement on last month’s G7 summit.

It came ahead of an attempt tonight by rebel MPs to try and take control of the Parliamentary agenda and block a no-deal.

Mr Johnson has said he will call a snap election if he is defeated by the alliance of cross-party MPs.

In a resignation letter address to the Prime Minister, and shared on Twitter, the Bracknell MP wrote

Over 27 years ago I joined the Conservative & Unionist party led by Sir John Major. Since 2010 I have had the privilege of representing the Bracknell Constituency. The party I joined in 1992 is not the party I am leaving today.

This Conservative government is aggressively pursuing a damaging Brexit in unprincipled ways. It is putting lives and livelihoods at risk unnecessarily and it is wantonly endangering the integrity of the United Kingdom. More widely, it is undermining our country’s economy, democracy and role in the world. It is using political manipulation, bullying and lies. And it is doing these things in a deliberate and considered way.

That is why today I am joining Jo Swinson and the Liberal Democrats. I believe the Liberal Democrats are best placed to build the unifying and inspiring political force needed to heal our divisions, unleash our talents, equip us to take the opportunities and overcome the challenges that we face as a society – and leave our country and our world in a better place for the next generations.