There will be times when running commentary on Brexit has to break out from a trot into a sprint. This week is one of those.

The resignation of Sir Ivan Rogers as UK Permanent Representative to the EU has been widely reported. People seem more surprised than they should have been. It is not news that Rogers, a skilled and diligent official, was out of kilter with the three Tory Brexiteers Davies (Brexit), Fox (trade) and Johnson (foreign affairs). One can only imagine what he thinks of Andrea Leadsom (agriculture) and Priti Patel (overseas development), two even more ferociously anti-European ministers.

But the real reason he went, according to an impeccable source, is that the prime minister has ceased to listen to him – or at least, that she makes no effort to appear to hear what he has to say. This is foolish behaviour by Theresa May, as well as insulting. She is a cool fish. But not to consult and inform her chief negotiator in Brussels about her plans was bound to lead to a bust up.

Being an honourable man, who will be much missed in Brussels, Rogers was careful in his message to the UKREP staff not to point the finger directly at Downing Street. But he did say this, with stunning veracity: “We do not yet know what the Government will set as negotiating objectives for the UK’s relationship with the EU after exit”. And it is that statement that is left echoing throughout the chancelleries of Europe.

May promised MPs that she will set out her negotiating objectives early in the New Year. That speech cannot come soon enough. But do not expect her to bare all – not least because, as Rogers has exposed, there’s still more muddle than strategy in Whitehall.

The main purpose of the prime minister’s speech is to test the solidarity of her cabinet. Recent if weak signals suggest that she will row back from ‘hard Brexit’ – a tactic which, while provoking ravings from Ian Duncan Smith and Michael Gove outside the cabinet, she appears to have squared at least with Davies and Fox. (Johnson remains wholly unpredictable.)

The rest of Europe waits to learn about where the UK wishes to end up once it has left the EU. Definition of the framework for the future relationship is much more important than the technicalities of the Article 50 withdrawal agreement itself. The EU deserves to know very soon whether Brexit will settle Europe’s British problem for good or merely prolong the agony.

It is already taken for granted that the UK will not seek membership of the European Economic Area with full access to the single market. If May wishes to reverse that impression she will have to do so promptly and clearly in this forthcoming speech.

The prime minister needs to tell us if she wants to remain in the customs union, and if so whether continued membership of the customs union is to be temporary or permanent.

Above all, she needs to deal with the concept of an Association Agreement, and embrace or reject it. If she pitches for an Association Agreement along existing EU lines and according to precedent, her speech will be welcomed as meaning that the UK is keen to maintain political cooperation with the EU in matters of foreign policy, internal and external security and in fighting crime. An Association Agreement is also the framework inside which a deep and comprehensive free trade agreement would be negotiated.

By contrast, not to mention the possibility of an Association Agreement will be understood to mean that the UK is preparing to cast itself further adrift from its erstwhile partners than many, perhaps most of them would wish.

What May says now about an Association Agreement will also determine how much she needs to add at this stage about transitional arrangements. If she is positive about a future Association Agreement, the need for a smooth and possibly lengthy transition becomes straightforward. If she is negative, however, leaving the definition of Britain’s future landing zone uncertain, the mood in Brussels will harden against conceding anything to London but the shortest and most technical temporary arrangement.

The leaders of EU 27 gather in Malta on 3 February to mull over their future together without the Brits. In the present chaotic circumstances, a January speech by Theresa May would be much better than a February one.

Andrew Duff is a Visiting Fellow at the European Policy Centre and was a Liberal MEP 1999-2014. The original article can be found at https://andrewduff.blogactiv.eu/2016/09/ . twitter @andrewduffeu