We are in EU limbo. Escape could mean heaven or hell. . .

Why last weekend might we have recalled those famous words by Sir Robert Walpole in 1739: “They may ring their bells now. Before long they will be wringing their hands”? He was a Tory prime minister who had been reluctantly pushed by a wave of political hysteria into declaring a war on Spain which he rightly feared would end in disaster.

The truth is that the campaigns on both sides in the referendum were horribly caught out by the result, because neither had any plan for what to do next. David Cameron chose not to have an exit plan because he was convinced his Project Fear would carry the day.

Vote Leave rejected any exit plan because, as they repeatedly showed during the campaign, they hadn’t done their homework, they couldn’t agree on a plan and they just hoped they could wing it in the unlikely event of their winning.

Only towards the campaign’s end did people at last wake up to the fact that the only legal way to leave the EU is by invoking Article 50 of the Lisbon treaty (as first explained here in 2012). Only very belatedly did more clued-up commentators begin to recognise that the only sensible way forward is to ensure that we remain fully part of the single market as a member of the European Economic Area (EEA), so that leaving the EU does not disrupt our trade with the EU in any way.

The relevant image is that of a snakes and ladders board. Recognising Article 50 as the only way to start our two-year negotiations to leave merely puts us on square one of the board. To reach the goal of a satisfactory settlement requires correctly negotiating 99 more squares, with plenty of snakes and ladders intervening.

There are really in fact only two options before us. One, as I was first outlining in 2013, is that exhaustively set out in the blueprint produced by the Leave Allliance, which has been much pored over in Whitehall in recent weeks.

On invoking Article 50 we should begin our negotiations mindful that we are already in the EEA where, outside the EU, we intend to remain. This, along with an application to rejoin the European Free Trade Area, gives us an immediate, off-the-shelf solution to the trading problem. Furthermore, under Article 112 of the EEA Agreement, we would also have as they are called, such as Turkey and Morocco.

Although this might be portrayed as an attractive compromise, in fact it is a highly deceptive “snake”, because it leaves us still in the EU, but as only a second-class member, with all the disadvantages this would bring. Still subject to much of the supranational system we voted to escape, this would in some ways leave us even worse off than we are now.

The most disastrous possibility is that we could reach the end of our two-year negotiations without any agreement (which is why on invoking Article 50 we should immediately apply, as the rules allow, for a possible extension for as long as is needed to reach a proper agreement).

Otherwise we would be faced with the absurd situation where, after our having left the EU-28, remaining EU members, under the rules, would continue to be able to sell to us, but we would no longer have the paperwork necessary to export to them.

We have entered far more dangerous waters than most people realise. We need all the clear thinking and proper understanding of the rules which was so woefully lacking from the Vote Leave campaign, but which the coolerheaded Theresa May seemed to be offering when she said that “Brexit means Brexit”.

The only possible way to navigate to the top of that snakes and ladders board, and to give the British people the goal they voted for on June 23, is the first option above.

Let us hope those civil servants who have been studying will find that it is the way out of the labyrinth into which, for the right if not fully understood reasons, we have now placed ourselves.