Corbyn secures emergency debate tomorrow on need for MPs to approve military interventions – as it happened

• Theresa May has used a marathon statement to the Commons, lasting more than three hours, to defend her decision to order airstrikes against Syria. She faced widespread criticism from the opposition, mostly focused on her decision not consult parliament first, but Conservative MPs were overwhelmingly supportive and the deepest splits were on the Labour benches, where several prominent members of the party’s hawkish faction made a point of backing May, often with implicit criticism of Jeremy Corbyn. May sidestepped questions about whether she would guarantee MPs a vote on any future airstrikes, although she distanced herself from the argument from international development secretary Penny Mordaunt this morning about it being wrong for the executive to have to ask parliament to approve military interventions. (See 8.52pm.)

• Jeremy Corbyn has secured an emergency Commons debate tomorrow on the convention that parliament should have to approve military interventions. (See 8.07pm.) Another emergency debate on Syria, on a general motion tabled by the Labour MP Alison McGovern, is taking place now.

• Labour has released a five-page legal opinion that casts doubt on the government’s case for missile strikes against Syria, warning that the necessary standards to justify military action on humanitarian grounds had not been met.

• The cyberwar between the west and Russia has escalated after the UK and the US issued a joint alert accusing Moscow of mounting a “malicious” internet offensive that appeared to be aimed at espionage, stealing intellectual property and laying the foundation for an attack on infrastructure.

That’s all from me for today.

Thanks for the comments.

Here is the full text of Jeremy Corbyn’s statement applying for the emergency debate on the convention that parliament should approve military interventions.

I seek leave to propose that – in light of Friday’s air strikes in Syria – the House should urgently debate the important matter of the government’s obligations, under parliamentary convention, to seek the approval of the House before committing UK forces to pre-meditated, hostile, military action overseas.

The cabinet manual published by the government in 2011 confirms their acceptance of that convention and guarantees that the government will – I quote – “observe that convention except where there [is] an emergency and such action would not be appropriate.”

Two years ago, even while reneging on the government’s previous commitment to enshrine that convention in law, the then defence secretary [Michael Fallon] guaranteed in this House that the government would – and I quote: “keep parliament informed and ... of course seek its approval before deploying British forces in combat roles into a conflict situation.”

Members on all sides are therefore rightly concerned that no such approval was sought by the government prior to the pre-meditated air and missile strikes against Syrian government installations to which the UK was a party last Friday night, alongside the United States and France.

Indeed, this House was not only denied a vote, but did not even have the opportunity to question the government in advance:

• on the legal and evidential basis for their participation in this action;

• on the government’s new strategy in regards to Syrian intervention; or

• on why they acted before the ongoing inspection by the Office for the Prohibition of Chemical Weapons in Douma had concluded.

Members will also be concerned that these strikes have been explicitly presented – both by the government and by the United States – as a precursor to even stronger intervention against the Syrian regime if they judge that to be necessary.

Therefore, the government’s failure to seek – let alone obtain – parliamentary approval for these air strikes sets a precedent for potential and much more dangerous future action, not just in Syria, but in other countries where similar situations may arise.

I therefore ask, Mr Speaker, that you allow urgent consideration by this House of the government’s approach when it comes to the rights of parliament to debate and approve military action overseas, particularly in the context of last Friday’s air strikes in Syria.

John Bercow, the Speaker, is responding. He says this is an appropriate topic for an emergency debate under standing order 24.

Bercow says the debate will be held tomorrow, as the first item of business.

The debate will be on a motion saying the Commons has considered the matter set out in Jeremy Corbyn’s application. That means effectively it will be a debate reaffirming the convention that parliament should have to approve military interventions.

• Corbyn wins approval for emergency debate tomorrow on motion reaffirming the convention that parliament should have to approve military interventions.

What happens next?

We do not have the exact wording yet, so we do not know whether or not the government will back the motion.

The government still broadly accepts the convention that parliament should have to approve military interventions, subject to the proviso that ministers can order an attack without parliamentary backing if they think that is necessary. So theoretically they could vote for the Corbyn motion.

It is very hard to imagine it being worded in such as way ministers feel obliged to vote against. (It will probably be phrased along the lines “that this House has considered the convention that that the government must seek parliamentary approval before committing to planned military action” etc etc). More likely, the Conservatives will abstain.

But we will found out tomorrow.

Corbyn says, if the government is allowed to authorise airstrikes without getting parliamentary approval, that would set a dangerous precedent.

In the Commons, Jeremy Corbyn is now making an application for an emergency debate on Syria. He said it would be on the principle that the government should observe the convention that it seeks the approval of parliament for military action.

Andrea Leadsom, the leader of the Commons, has just delivered a short business statement. She did not announce a Syria debate later this week, as some of us were expecting. Instead she just said that the business originally scheduled for tonight, the second reading of the laser misuse (vehicles) bill, would be rescheduled.

May’s statement is finally over. It lasted for more than three hours. John Bercow, the Commons Speaker, says 140 backbenchers asked questions.

Sylvia Hernon, the independent MP for North Down, says the DUP do not speak for everyone in Northern Ireland. She says there are many people in Northern Ireland who were bitterly opposed to the decision to launch airstrikes without consulting parliament. She asks what the government is doing to avoid the risk of escalating the conflict in Syria, and to avoid the UK facing retaliation.

May says the government acted in a way to minimise the risk of escalating the conflict.

The SNP’s Alison Thewliss says the missiles used by the UK in the airstrikes would have cost more than £6m in total. How much is the government spending rebuilding the region?

May says the government has spent more than £2bn on aid for those affected by the conflict.

ITV’s Paul Brand has found a mixed bunch at the Stop the War demonstration.

Back in the Commons, Labour’s Toby Perkins asks why the government is prepared to intervene militarily to protect the victims of chemical weapons but not the victims of conventional weapons.

May says the government is not trying to resolve the civil war by military means. That is a matter for the diplomatic process, she says.

More from the protest outside the House of Commons. These are from CND, the Campaign for Nuclear Disarmament.