Brexit: Sir Ivan Rogers warns of humungous task. Watch out. It's going to get very bumpy

The complexities of trade, the EU budget, international treaties and more mean the process will take very much longer than 2 years and the instability created will inevitably shake the economy and markets

Sir Ivan Rogers (EPA)

Brexiteers don’t much like Sir Ivan Rogers, who abruptly left his post as the UK’s ambassador to the EU last month.

When you live in Brexit la la land and have told the nation that everything will jolly and wonderful and that the economy will just fly after Britain sails off into the middle of the Atlantic Ocean to bump uglies with Donald Trump, it can be quite disconcerting to hear a neutral party saying it might not end up like that.

Sir Ivan said his warning that European leaders fear it might be the mid-2020s before a trade deal between the EU and Brexitland is fixed up, was contained in a briefing note to the PM. He did not know, he told MPs on the House of Commons European Scrutiny Committee, how it came to be made public.

That may be true, but he also, as a senior civil servant, will have been well aware that these things have a nasty habit of getting out if you put them down on paper, even if you are only doing your job by doing so.

Just as details about the EU exut negotiation the UK is about to embark upon are going to get out, probably every time there’s a session.

One of Theresa May’s more amusing conceits is her repeated insistence that she is not going to give a "running commentary" on the discussions. We’re going to get one anyway.

Journalists covering them will need to be issued with rain coats to cope with the level of leaking. So are the traders, whose screens will be over heating as the various markets they cover react to the news reports.

If the Brexit project crashes and burns in public, some of those markets are going to crash and burn with it and we’ll all get seats to watch one of the scariest horror movies since William Friedkin wandered over to his special effects people and said: “I’d quite like to see if we can make it so Linda Blair’s head spins 360 degrees. That’d give me a really iconic scene for The Exorcist. Think you could manage it?”

No longer shackled by his responsibilities as an ambassador, Sir Ivan described the task of extricating Britain from the EU as “humungous” and warned that talks are likely to get feisty with "name calling" and even "fist fighting".

No kidding. With Boris Johnson, Liam Fox and David “any disagreement with me is against the will of the British people” Davis in charge, how could it be any other way?

Cheered on by the tabloid press every time they snarl, how do you think this is going to end?

Part of the problem, as Sir Ivan warned, is that no one’s quite sure where to start from, before they even get to some of the knottier practical issues, such as trade, or the EU budget, or the acquired rights of EU citizens (which should have been guaranteed already) or the impact of Brexit on international treaties.

They are going to tie ministers and their civil servants up in knots. To have told people it can all be done in two years was foolish in the extreme on the part of the Government.

With all the uncertainty that will created during the process, the economy is almost inevitably going to start shuddering. The pound will bounce up and down like a ball in the hands of Steph Curry in response to almost every leak. “We just need some certainty,” will be the cry of business leaders. Terribly sorry, but there’s none of that to be had.

With jobs almost sure to be threatened, what do you do if you, as a Government, start to see a bad situation developing that you have overseen the creation of, having ignored all the warnings and advice given to you by people like Sir Ivan?

You force them out. Then you blow a lot of smoke and look for a scapegoat to pin the blame on. You then shout very loudly at that scapegoat, with the help of your friends from the tabloids.

Brussels is already a bogeyman. It’s going to be held up as Exorcist baddie Pazuzu and blamed for all the economic problems that the Government has created for itself as relations deteriorate. Unless, that is, the grown ups somehow find a way of taking control. If they do, it’ll still get very messy. But unfortunately most of them are like Sir Ivan: On the outside looking in.