UK PM Andy Burnham wants to get closer to the EU – but he shouldn't expect a smooth rideLaura Kuenssberg talks to government insiders about the prime minister opening the conversation about the UK rejoining the EU.13 hrs agoBBC InDepth

Déjà vu? The Eurostar has been booked. Strategic leaks of draft agreements have started.

The EU’s former Brexit negotiator Michel Barnier is warning the UK it can’t have it all and it will not be able to rejoin its single market “à la carte”.

Naturally, there is even a row about smoky bacon crisps – an argument between the UK and EU about food labelling has become a classic of the genre. Remember the bendy banana? Or the so-called sausage war between Boris Johnson and Emmanuel Macron?

It’s a clash between those arguing it’s worth swallowing some new rules to ease trade with the continent, or those whose message to Brussels is, “hands off our snacks” – even though we are not actually in the EU anymore.

That meeting is not supposed to be about whether the UK might one day go back in. The prime minister has suggested that is his long-term ambition – but is he really ready for what is to come?

First, Burnham inherited the broad deal that’s likely to be signed. The UK and EU were originally meant to mint a new and, they hope, improved agreement back in May, then in July, and well, political upheavals mean one thing for getting things done – delay.

But that means the outlines of a new agreement have been clear for many months, an approach based on “closer alignment” as Sir Keir Starmer proclaimed to us at the start of the year.

So if the prime minister hails agreement, spare a thought for those who started the work to get it this far many months ago.

One source familiar with the negotiations told me, “They are 90% there”, with agreements designed to make life easier for food producers, a deal on emissions trading which could help manufacturers, and new arrangements for youth visas (although it’s understood there is still haggling over putting a cap on the numbers).

An EU source close to the process said: “The bone of contention is a cap – we proposed 150,000, the UK proposed 50,000 – but we would expect to reach a compromise”, even though it has been “very tense” on both sides.

A last-minute call from the EU to cut tuition fees for its students is expected to be parked for now with more months of discussion to come. Another fine tradition – agree what you can, but file some tough stuff away for future chat.

There are dilemmas too on the EU’s so-called “Made in Europe” plans – draft laws to protect its industries from being hammered by Chinese competition. The purpose is clear – to help the economy grow, with the prime minister quoting figures that suggest closer ties to the EU without going back in could add 0.4 percent to GDP.

But as the tabloid-friendly row over salty snacks illustrates, making it easier to do business with the bloc doesn’t come without a cost, and a political awkwardness.

Talking to my colleague, the BBC’s Business editor Simon Jack this week, the prime minister admitted the UK would have to follow more EU rules. “That’s where we’ve ended up,” Burnham acknowledged.

And whatever your feelings on the matter, that lands us slap-bang back in the middle of the eternal dilemma of the relationship between the UK and the European Union.

How much control is the UK willing to lose in the hope of bigger wins? Even when it comes to a relatively limited number of important issues that are on the table in the current discussions?

The prime minister has scrapped the limits of this troubled conversation, not just suggesting a closer relationship with the relatively dry and technical changes being discussed right now, but dangling the possibility of going back into the bloc one day.

Suggesting freedom of movement again, unlimited immigration for Brits who want to live or work on the continent and vice versa. That’s after repeated promises, including from him, that that sometimes toxic debate would not be reopened.

What is he up to? It seems the prime minister’s main line of thinking is that with problems like long passport queues and red tape for business it is right and proper to try to sort them out.

That is after all, what Rishi Sunak and then Sir Keir Starmer tried to do.

But his willingness to contemplate going a lot further is based on a belief that the public’s attitude has shifted – if you look at polling it does suggest that a majority of voters support going back into the EU.

It just so happens his own long-time conviction is to go back into the bloc one day. And that idea chimes not just with many Labour activists and members, but also with the Lib Dems, Greens and SNP – whose voters he’d be only too happy to peel off.

But hang on, don’t let Burnham’s easy-breezy style mask that just casually mentioning he is open to us going back into the EU in the run up to this summit is a huge and difficult thing. Whatever relationship he truly wants to seek, and even those involved in the conversations aren’t quite sure he is even sure, don’t expect a smooth ride from the EU.

In an interview you can see tomorrow, the EU’s chief negotiator last time, Michel Barnier, told me the UK cannot pick and choose the relationship “à la carte”.

If we wanted to go back in, he told me, the UK could forget the famous rebate, and there is no way to be in the huge trading bloc, the single market, without accepting freedom of movement.

One government figure told me, even now dealing with the EU there are “lots of very warm words, but quite a lot of arms folded”.

An EU insider told me the mood has certainly changed. “There is big scope getting closer to the EU, but nobody wants it to be toxic… we wonder, does he know what he is doing?”

Last time round, the majority of businesses, with some notable noisy outliers, were keen to stay in the EU. But after several years having to make the relationship work, and spend money on rearranging how they do business, that might not translate into such solid support if the prime minister does choose to pursue a return to the EU.

One prominent business figure explains: “You’re a langoustine exporter from Ullapool? Yes, please. You are manufacturing and making that car? Yes, get me back in. You’re a drugs manufacturer? Well, sort of, yes and no. You’re in financial services? We’ve spent the money. Do we want to unpick this?”

There are prominent backers of the idea of a return to the EU, if Burnham himself decides to make that case. The former Chancellor Rachel Reeves and the London Mayor Sadiq Khan make the case as well.

We’ve already talked about the Lib Dems, the Greens, the SNP, and Plaid Cymru being up for it, as are many Labour MPs and ministers.

But the political risks of arguing for a return to the union are, frankly, enormous. Labour is divided, just as the country could be, whatever the current polls suggest.

One former Labour minister told me, “the prime minister wants us to go back in, but it is a very hazardous route”, saying of the party’s broadly pro-European rank and file: “Nobody wants to criticise Andy, but if it blows open they won’t all be in the same place”.

One cabinet minister’s eyes rolled so violently when I asked if they fancied another referendum they nearly went into the back of their head. And it is a safe bet that if the prime minister really decides to pursue a return that there’d be a ferocious pushback from the other side.

The Conservatives and Reform are already howling with protest about the deal expected to be signed this month.

Kemi Badenoch criticised the prime minister for “unpicking the deal this country signed with the EU a decade after the referendum” adding, “he is not going to get a better deal… it’s not just that the EU are tough negotiators, he has already revealed his entire negotiating hand.”

Meanwhile Reform UK deputy leader Richard Tice accused Burnham of “trying to sneak us back into Brussels via the back door”, and said Reform would “never let this betrayal go unchallenged”.

And you can expect similar financial arguments to be made as last time round. Vote Leave was always only too happy to have noisy clashes over the cash the UK paid to be part of the EU – that £350m – the gross contribution, not the net.

But every argument about the amount reminded the public that the UK did spend millions, even if the figure was officially judged as misleading.

While EU leaders might want to be helpful to Burnham, the Czech prime minister’s comments on the issue were rather unhelpful. Asked recently if he’d like to see the UK go back his answer was, “Yes, of course – we need more money”.

There could be enormous opportunity for the economy, important support for the UK’s security, and a boost for the prime minister’s backing among some voters if he does indeed end up deciding he will make the case for the UK to rejoin the European Union.

But it would be a heck of a gamble. A decade ago, a relatively popular prime minister named David Cameron with expert communication skills wanted to reset the UK’s relationship with the EU. That blew up his leadership, unleashing a series of political disasters that saw him off, and dogged his party for years.

Andy Burnham is a relatively popular prime minister too, also confident in his ability to communicate with you, and serious about improving our ties with the EU. But in his party, there are those preaching caution about opening this conversation.

The successes or failures of the impending summit will give him, and the rest of us, a taste of what might lie ahead.

Top picture credit: Getty editorial

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