Brexit: Is fishing the next big argument in the talks?
It has always been an emotional issue in the UK's relationship with the European Union.
Fishing: a symbol of the sovereignty that supporters of Brexit say will now be regained.
The EU has already announced that an agreement on fisheries is a pre-condition for the kind of free trade deal, with no tariffs or quotas, which both sides say they will try to work towards.
But the UK says any such agreement must be based on the understanding that, after Brexit, "British fishing grounds are first and foremost for British boats".
So, there could be troubled waters ahead.
How do fishing controls work?
During the post-Brexit transition period until the end of this year, fishing will continue to be governed by the EU's Common Fisheries Policy (CFP).
That means the fishing fleets of every country have full access to each other's waters, apart from the first 12 nautical miles out from the coast.
But they can't catch whatever they like. EU ministers gather for marathon talks every December to haggle over the volume of fish that can be caught from each stock.
National quotas are then divided up using historical data going back to the 1970s, when the UK got what its fishing industry says was a bad deal.
It's further complicated by the fact that parts of the British quota have been sold off by British skippers to boats based elsewhere in the EU.
In England, for example, more than half the quota is in foreign hands.
Overall, more than 60% of the tonnage landed from British waters is caught by foreign boats.
So, Brexit is a chance for a fresh start.
Outside the EU, as an "independent coastal state", the UK will control what's known as an exclusive economic zone (EEZ), a vast maritime territory stretching up to 200 nautical miles into the North Atlantic.
The government wants to hold annual talks with the EU on access to those UK waters and on quotas. That's what other independent coastal states like Norway do.
And fishing communities in the UK, which were strong supporters of the campaign to leave, are insisting on this basic change.
But because UK waters are so important, and so bountiful, the EU is under pressure from its fishing communities to maintain the status quo.
It wants the UK to grant the same level of access there is now, with only gradual change envisaged, in order to "avoid economic dislocation for EU fishermen that have traditionally fished in the UK waters".
The EU also wants to divide up the amounts that each country's boats are allowed to catch in a way that will not be up for negotiation every year, and which cannot be changed unless both the UK and the EU agree.
Access to markets
Given that the UK has left the EU in order to set its own rules, it might appear to be in the driving seat in this argument (or should that be at the helm?)
But it's not just about where fish can be caught - it's also about where fish can be sold.
This is particularly important, because most of the fish landed by UK fishermen is exported (while most of the fish eaten in the UK is imported).
In 2018 the UK exported 448,000 tonnes of fish. The total catch by UK vessels into UK ports was 395,000 tonnes. About 100,000 tonnes of UK exports were salmon (which doesn't count in landings figures).
Three quarters of UK fish exports are sold in the European Union, and some parts of the industry - such as shellfish - would collapse if they were suddenly faced with tariffs or taxes on their produce.
Proportion of UK fish exports going to the EU in 2018
The UK says access to markets should be nothing to do with access to fishing waters, but the EU is already making that link explicit.
Without a deal on fish, it insists, there will be no special access to the single market.
Remember that a deal on fish would not just affect fishermen (and women), of which there were an estimated 11,961 across the UK in 2018.
There were also about 18,000 people employed at fish processing sites in 2016.
And it's not just about fishing at sea - there are also inland sites such as salmon fish farms, which would be affected by any deal.
Plenty of other issues need to be taken into consideration, including:
- Protecting fish stocks and preventing over-fishing
- Taking account of the different priorities of big industrial trawlers and smaller boats
- Working out how fishing ranks alongside other issues in trade talks.
- Nations such as Scotland wanting to go their own way
It is a complex picture.
And it's worth remembering that fishing is only a tiny fraction of the overall economy both in the UK (less than 0.1%) and in the rest of the EU (some landlocked countries have no fishing fleets at all).
According to the Office for National Statistics, fishing was worth £784m to the UK economy in 2018. By comparison, the financial services industry was worth £132bn.
£784mcontribution of fishing to UK GDP
£132,000mfrom financial services
But fishing still has political power.
The EU's negotiating mandate is only a draft, produced by the European Commission. The language it contains is already being toughened up as member states with big fishing communities have their say.
The UK government will also be under enormous pressure not to give ground.
If there is any compromise to be found, it would probably involve the UK guaranteeing a certain level of access to EU boats, which is lower (but not much lower) than they have now.
The two sides had already agreed, in the political declaration that accompanied the EU withdrawal agreement, that they would try to reach a deal on fisheries by 1 July this year.
Given the tight timescale, and the political sensitivities on both sides, it looks set to generate one of the first (but not the last) big arguments of these negotiations.