There is currently some kerfuffle about whether the EU27 and UK will proceed to trade talks in October. It is suggested that the EU does not believe there has been sufficient progress on EU citizens’ rights, the “divorce bill” and the Irish border for it to be appropriate to move to trade talks.

This is a deeply confused claim. It is simply not feasible to make any final agreement on EU citizens’ rights, the “divorce bill” or the Irish border question without first knowing what sort of trade deal the EU and UK will have post-Brexit. They are not separate questions such that one can be settled before moving to the other.

Let’s see why not. First consider the Irish border. The key Irish border question is to resolve how we would manage the movements of goods and services over the border post-Brexit. The UK is not going to be in the customs union, so there will need to be some system of customs clearance. That could be done via some highly aligned fast-track procedure just before goods set off, probably electronically (as indeed has been possible for UK customs clearance since the 1990s). If we didn’t do things that way then another alternative, if feasible, would be for the UK to do the EU’s controls for it inside the UK, and for the EU to do the UK’s checks inside the EU. A third alternative would be to do all customs checks after arrival.

The UK has noted both of the pre-checking alternatives. Until we know what the nature is of the customs challenge – eg are we collecting tariffs, or checking regulatory compliance, or just checking rules of origin? – what more is there to be said? What else could the EU possibly have in mind as an agreement over the Irish border that didn’t involve knowing the trading arrangements? Giving Northern Ireland to France? Eire re-joining the UK? Ireland leaving the EU alongside the UK to form a new trade area? There being an internal border inside the UK? Every alternative that does not involve knowing the trading arrangements seems absurd.

Similarly, we can’t come to a final financial agreement until we know the trading arrangements. There are several reasons for this, but the simplest to understand is the following. The main mechanism by which the UK will be giving extra money to the EU is through transition. Transition arrangements will be helpful for businesses on both sides to adjust to life when the UK is outside the EU. They will also help the EU adjust to life without UK financial contributions. We should be just as flexible and reasonable in winding down contributions as we hope the EU27 will be in agreeing commercial transition. So we should be providing some extra money under this auspice.

But we cannot agree transitional arrangements until we know what we are transitioning to. Otherwise they are not transitional arrangements at all – they are, instead, an interim or intermediate deal. No interim deal will be acceptable. Transition is fine, provided we know what we are transitioning to. But what we are transitioning to is the new trading terms of the new trade deal we need to agree. Before trade talks we cannot agree a transitional arrangement so cannot agree what (if anything) to pay in the transition period and so cannot come to a final financial settlement.

The fact we cannot come to a final financial settlement also means we cannot finalise EU citizens rights, because some of those may depend upon the financial agreement reached. Some EU citizen rights should have been offered unilaterally immediately after the referendum and they do not require any financial settlement now – namely the right to remain and to work. We should also offer a fast-track right to EU citizens to become British citizens (they came here as our fellow citizens and should be entitled to continue being our fellow – now British – citizens if they want to be). But many other rights for EU citizens who choose not to become British citizens are reasonable matters for negotiation.

A very simple case is the right to vote in local elections. Post-Brexit an EU citizen who has freely chosen not to be a British citizen has chosen to be fundamentally a visitor. We might grant visitors a vote and we might not. There is not deep principle that says we must or must not. It’s a matter for negotiation.

Another issue is the entitlement to contributory benefits. One natural way to deal with that would be for EU citizens in the UK who had made relevant contributions in their own countries to be able to port that contribution record to the UK and thus build entitlement here. But those monies will have been paid to their home state (or state agencies) in the EU. So if the entitlement is ported the governments ought to pay the relevant sum to the UK government, equivalent to the value of the amount the citizen would have paid if the contributions had been made in the UK.

Well, for that to happen we need to make a financial deal with the EU. But we’ve already explained to the EU that we cannot make a final financial deal with the EU, including financial contributions during transition, until we have agreed what trade arrangements we are transitioning to.

There are reasons of negotiating leverage for preferring to have trade talks at the same time as these other matters as well. But even if there were not, we have seen above that there is no way to agree these issues without knowing the trade deal (of which we may hear more on the UK’s ideas when it publishes its trade position papers shortly). Saying we cannot discuss a trade deal until we have agreed these matters is nothing more than empty obstructionism.

Come on, everyone. You’re better than this. Let’s get on with the trade talks and through them resolve these other matters at the same time. There’s a friendly mutually-beneficial deal to do. Let’s get it done.