Henry Newman is Director of Open Europe.

At a time when all politics is in flux, and it sometimes seems that literally anything could happen, there are still some certainties. One is that the personal vanity of the Speaker knows few bounds. Yesterday he demonstrated this.

In a statement, John Bercow raised the pressure on the Government and suggested that he would use his own judgement to determine whether Theresa May’s Brexit deal could be put a third time to Parliament or not. He drew on a rule in Erskine May – the House of Commons procedure manual – which says that a motion cannot be repeatedly introduced if it has previously been rejected by MPs.

Bercow was skewered by Mark Francois who pointed out that the rule also applies to amendments, and so, according to the same logic, the Speaker ought not to allow further divisions on a second referendum (which has previously been voted down by the Commons), nor indeed on a customs union, the Single Market and so on. Francois is correct. Erskine May actually reads: “a motion or amendment which is the same, in substance, as a question which has been decided during the same session may not be brought forward again during the same session”.

But substance isn’t really the issue here. Bercow has huge prerogative powers. He can apply these powers inconsistently and there’s little anyone can do. His intention is to put himself front of centre of the national (and international) Brexit drama, even if it means turning a political crisis into a constitutional crisis. Incredibly, the Speaker’s intervention was celebrated by some Eurosceptics.

Brexiteer MPs need to wake up and smell the coffee. The options have fundamentally narrowed. As I have warned before, the Speaker is no ally of Brexit, let alone a hard Brexit or a No Deal. He is willing to do whatever is necessary – either bending procedure and convention, or sticking rigorously to it – so as to frustrate the Government’s attempt to deliver Brexit. This matters because in a hung Parliament the Speaker takes on huge powers. The Government has almost no working majority. Its ability to deliver any decent Brexit is profoundly at risk.

And yet there are far too many Conservative MPs who still don’t seem to recognise that May’s Brexit deal is the hardest Brexit now on offer. The danger with these MPs continuing to withhold their support, is that they will ensure we either lose Brexit altogether or more likely end up with a far softer form of it.

If you don’t like the regulatory alignment of the backstop, just wait till you see what wide-ranging alignment the Single Market or a so-called Common Market 2.0 would mean (as well as little ability to control free movement). If you think we might get stuck in a customs union via the backstop, I’d disagree with you, but suggest you imagine what it would mean to have a permanent customs union amended on top of the deal. Surely, it’s better to have a path out a customs union however uncertain rather than no path out?

In two days’ time Theresa May will go to Brussels to beg the EU to grant an extension to Article 50. This is a profound national humiliation and an abject failure of her Brexit plan. Many sides of the Conservative Party share blame here – the Government for its lamentable Brexit strategy, Remain-minded ministers who abstained on key votes, and backbench Brexiteer MPs who refuse to accept any reasonable compromise, even as options shift.

Boris Johnson’s suggestion that the Prime Minister should use the European Council meeting to secure further changes to the backstop is fanciful. The ERG argument has long been that No Deal had to be kept on the table so as to secure further concessions. If you accept that, then you should also accept that according to that reasoning, now that Parliament has taken No Deal off the table, the EU will be unlikely to concede further.

Some Eurosceptics seem convinced that we will leave anyway on 29th March because that’s the current law. Unfortunately, that won’t be true if the Prime Minister agrees an extension in Brussels. At that point our international law position will be that we will still be members of the EU. Anyway, it seems likely that a majority would be easily found to approve a statutory instrument to change the exit date – it would not be capable of being amended.

Other Eurosceptics see a long extension as a possible path to No Deal. This is far-fetched. What is far more likely is that Parliament will impose a softer Brexit than the Prime Minister’s deal over the next few days or weeks. That would be a much worse outcome.

An extension may offer a route to a snap election. But that would mean May leading the party into another contest on a manifesto centred on her deal – surely the very thing her critics would abhor. She would either win, in which case it would be her deal. Or she could lose – in which case losing Brexit would be the least of our worries.

One senior backbench Eurosceptic seems to believe that in a future leadership contest any deal would be cast aside. According to this argument, it doesn’t matter if the Commons agrees Norway Plus – a future leader will reject it. But if you believe that a deal can be ditched after it’s signed, then why not sign the current deal which is obviously a better deal than Norway Plus (and if you got stuck in the backstop you could then junk it then)? The only answer is ambition.

Over the last few days, more and more erstwhile critics are coming around to the deal. ConservativeHome’s Mark Wallace writes that we have reached the point where MPs should vote for it. We have also seen Lord Trimble and Lord Bew arguing that the changes secured at Strasbourg have provided them with sufficient reassurance to now back the deal – for more on that, see a piece by Professor Guglielmo Verdirame QC on the Vienna Convention and the backstop. Former Party leader Lord Howard has endorsed the deal, while Lord Lamont said that “to assert as some Eurosceptics do that it is preferable to remain in the EU than to accept Mrs May’s deal is absurd”.

There’s precious little time left. Critics of the deal need to compromise and accept the actual choices on offer now. They may not agree with me that the deal is better than many are willing to admit, but they ought to see that it’s far preferable to either a permanent customs union or a Common Market 2.0 (as Norway Plus has been re-branded). It’s also worth going back again to the substance of the actual detail. Too often critics seem not to recognise that even in a worst-case scenario, the backstop, we would be free of EU regulations in most areas and under no obligation to agree new EU rules on goods and agriculture anywhere in the UK. We also now know that the EU cannot use the backstop as a ‘trap’ to force us to make further concessions.

If the DUP move to back the deal then Conservative critics of it, on both sides of the argument, Leave and Remain, should accept the need for compromise for the sake of the country, as well as the Conservative Party. If there’s clear support in the Commons, May should be able to reintroduce her deal one further time, probably after this week’s European Council. MPs will have one more chance to deliver Brexit. If they don’t take it, Bercow will try to ensure that there may not be another.