Boris Johnson likes to say Brexit's done. But it's far from over and the next chapter in the post-Brexit battle was opened this week as the UK and the EU set out their blueprints for trade talks ahead of the negotiations, which begin on Monday.

Both sides want a free trade deal that removes tariffs and quotas on goods. But there remain big hurdles which will involve compromise on both sides.

Some of the biggest flashpoints surround the prime minister's insistence on Britain's sovereignty and legal autonomy against the EU's desire to bind the UK closely to existing rules.

One of the biggest barriers to a deal is Brussels' demand that the UK agrees to maintain "common high standards" - otherwise known as "level playing field" arrangements - to make sure the UK doesn't use leaving the EU to undercut its former partners.

The EU is also demanding the UK use EU standards as "a reference point" in its own laws and stays in line with them; not just now, but in the future too.


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The UK is clear in its negotiating mandate that it will not accept being legally tied to EU standards in any way - be that on state aid, employment, or environmental protections.

It will maintain current labour and environmental standards - but on its own terms, not the EU's.

Which runs into the second big faultline between the two sides: the role of the European Court of Justice in policing a new trade deal.

The EU wants its own court to be able to issue binding rulings on disputes, while the UK is adamant the ECJ will "not have any jurisdiction in the UK".

The "taking back control" theme of the Vote Leave campaign - spearheaded by Mr Johnson - also runs through another big flashpoint in the talks: fishing.

The EU says the trade deal must include fishing rights and wants a long-term deal to give EU fishermen access to UK waters.

The UK insists it will become an "independent coastal state" which will agree annual negotiations to access waters.

The EU's coastal states such as France won't settle for that.

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Level playing field arrangements, the ECJ and fishing rights - these are just three of a number of stumbling blocks.

But trade experts and politicians on both sides tell me they think the two sides can strike a deal, in part because of the scaled-down ambition between Mr Johnson's deal against that of his predecessor Theresa May's.

"The difference between the May approach and the Johnson approach is that Theresa May always wanted to find a halfway house," said Sam Lowe, research fellow at the Centre for European Reform think-tank.

"She wanted a way of leaving the EU, giving the people who voted for Brexit what they wanted on the sovereignty front but mitigating the economic consequences.

"But the Boris Johnson approach is to say we're leaving the EU, we're going to go for a model that the EU acknowledges is on the table, a Canada-style free trade agreement.

"And, yes, there's going to be an economic cost but it's worth it because we'll have the freedom to intervene in the economy as we see fit and the freedom to strike free trade agreements, and in the long run it'll be worth it - trust us."

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And much is being taken on trust. Because the bigger unknown - beyond whether or not the two sides can hammer out a deal - is what it means for the UK economy.

The Brexit wars of last Autumn may feel a long time ago.

But it is only a matter of months since former Conservative cabinet ministers such as the ex-chancellor Philip Hammond sacrificed their careers to avoid the sort of no trade deal Brexit the government is now openly talking about.

They worried about the possible economic risks. They wanted a compromise deal along the lines of the May offer.

But Mr Johnson won the election emphatically on his promise to "take back control of our laws and borders".

His is a Brexit in which sovereignty trumps all else.

Friction on the borders and a hit to the economy is a price worth paying in return for British autonomy.

But the government is unwilling to put flesh on those bones.

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In the spring, ministers will consult businesses and economists to feed into a consultation on the "economic implications of the future relationship".

But the government is not committing to publishing the outcome.

The government seems to be saying it accepts friction as a price worth paying for sovereignty, and yet doesn't want to actually spell out the cost to the public.

The most recent Treasury projections - from November 2018 - said a Canada-style trade deal could shave 5% off economic growth over 15 years, while the absence of a deal could result in an 8% hit by 2035.

Now the negotiating mandates are out, over the next three months the two sides will be tussling over the terms of any trade deal.

But Mr Johnson has this week formally rejected the close relationship the EU had offered.

He wants sovereignty and he wants the EU to know he's prepared to get it - whatever the cost.