In 38 years working in Westminster, I've never seen it this bad – backbenchers are right to try to seize control

I’m not holding my breath, but if May and Corbyn did ever drag themselves to the same table, they would have more in common than they would like to admit

“You are not children in the playground, you are legislators,” boomed Geoffrey Cox, the attorney general, before the naughty kids rejected Theresa May’s Brexit deal by 230 votes.

Yet it is the leadership of both main parties that are acting like children. May and Jeremy Corbyn can’t even agree on whether to meet. The prime minister left the opposition leader off her guest list when she invited “senior parliamentarians” for talks aimed at breaking the Brexit deadlock. When she belatedly included him, Corbyn refused to attend unless she first took a no-deal exit off the table. Both leaders were wrong to set preconditions.

We have a government that can’t govern and an opposition that can barely oppose. In 38 years as a Westminster journalist, I can’t recall a time when both main party leaderships performed so badly at the same time. Normally, there’s a see-saw effect; one side benefits from the misfortunes of the other. Now it’s stuck in the middle.

This week showed how Brexit has turned politics upside down. May suffered the biggest Commons defeat in history on her signature policy but the question of her resigning was hardly mentioned. Her party can’t remove her because her MPs tried and failed last month; they can’t have another go for 12 months.

Normal cabinet discipline has collapsed. May doesn’t dare talk about her Plan B with ministers for fear it would immediately leak. Both May and Corbyn put off the crunch decisions and are not honest with voters about Brexit, putting their own survival first as they dodge the bullets from their own deeply divided parties.

Brexit has cut a swathe through party discipline too. Symmetrically, both leaders are threatened with resignations today. Some 20 ministers might quit unless May gives them a free vote on backbench plans to take control of the process. And 12 Labour frontbenchers might quit if Corbyn comes off the fence and implements his party’s policy by calling for a referendum.

I’m not holding my breath, but if May and Corbyn did ever drag themselves to the same table, they would have more in common than they would like to admit. They are tribal animals, and not inclusive. They both have a stubborn streak. They prefer denial to changing their public positions, putting off the evil day until the last possible moment.

To fill the vacuum of leadership, parliament plans an unprecedented power grab, with the help of a Commons speaker who is also rewriting the rules of the game. John Bercow is accused of anti-Tory and anti-Brexit bias. Infantile ministers plot their revenge by denying him the traditional peerage when he steps down. Have they nothing better to do at a moment of national crisis?

The prime minister’s cross-party talks are going nowhere. Her idea of a fireside chat is to read from a script, as some MPs discovered this week. MPs who met her report that she seems paralysed by her fear of two options: a no-deal Brexit and no Brexit. Allies insist May is genuinely exploring the prospects for a consensus across the parties. But I suspect her other aim is to remind Tory Eurosceptics and the DUP there will be a soft Brexit or no Brexit unless they swallow a tweaked version of her deal. I noticed that the MPs with the broadest smiles after meeting May were the hardline Brexiteers.

I wouldn’t be surprised if she told the Commons on Monday she has tried but failed to find a cross-party consensus that would implement the 2016 referendum result – her interpretation of it, that is. And that she is heading back to Brussels to seek changes to the backstop to prevent a hard Irish border. Nothing has changed, again.

Backbenchers are right to try to seize control. Also on Monday, Labour’s Yvette Cooper will publish a bill to allow a group of MPs to find a compromise and be able to force the government to seek an extension to the Article 50 process beyond 29 March if no agreement is reached by the end of February. Her bill will supersede the one planned by Tory Nick Boles, who will now back hers. To allow it to pass, backbenchers would temporarily suspend Commons rules to allow them to fix the timetable rather than the government. May would be appalled at this unprecedented loss of power but might not be able to stop it. If she was serious about building consensus, she would give a free vote to her MPs, including ministers.

The “children” attacked by the attorney general must now prove that they are the grown-ups. They will have to resolve this crisis; it is increasingly clear that May and Corbyn can’t.