IF ANYONE thought Brexit would be straightforward, those hopes were dispelled this week.

The process of negotiating the UK's exit from the EU has as much skulduggery and nastiness as an episode of 'Game of Thrones', not helped by those negotiating on both sides clearly neither liking nor respecting each other. A further layer of problems is that those leading the negotiations do not seem to have their respective sides fully behind them.

Despite losing its majority, the Conservative party is as divided over Europe as it was back when John Major was prime minister and the eurosceptics were out to undermine him. On the other side, the European Commission is taking a tough stance, because it does not want leaving the EU to be seen as an easy option for other countries.

However key players, including France and Germany, are concerned about the trade consequences of alienating the UK to the degree that it turns elsewhere for the products it needs to import. This has made the negotiations messy, as UK planning and wishful thinking comes up against European intransigence. The only certainty in the negotiations is that things will get a lot worse before there is even a faint hope of them getting better.

Farmers, like other businesses, are bystanders in this political game, and the outcome will decide the prosperity or otherwise of their businesses after Brexit in 2019. Politicians can debate how long the transitional arrangements will last, but in a long term business like agriculture, it does not really matter whether those last one or five years. The long term challenge remains a firm basis upon which the industry can trade. While support arrangements are important, it is the market that will ultimately decide whether Brexit succeeds beyond reducing marginally the number of foreign nationals coming to the UK.

This all makes a report from the Agrifood and Biosciences Institute (AFBI) in Northern Ireland on the market consequences of Brexit interesting reading. Like any economic analysis, it depends on a lot of assumptions, but it uses a joint US/AFBI financial model to tease out the consequences of the three main trade options on the table.

These are a special deal with the EU-27, allowing continued access to the single market; trading on the basis of World Trade Organisation most favoured nation (MFN) rules; and the truly radical option of the UK offering tariff free access to its market, in the hope others would reciprocate and give it tariff free access to their markets.

Of these options the latter is the most unlikely, and that is welcome news for the farming industry. Tariff free trading would devastate UK farm prices, with reductions of up to 45% for beef, 30% for lamb and 10% plus reductions for other enterprises. Without a massive increase in support, far above anything the CAP ever delivered, this would leave UK agriculture in an impossible financial position.

The comfortable option of remaining in the single market would have a minimal impact on farm prices. These would be reduced slightly, by between 1% and 3%, by the extra costs of compliance with EU rules, because the UK would be outside the CAP. This is what most people expected when the Brexit decision was made, but the government in London has made clear it will leave the customs union.

It could still make a deal to access the single market, but that is looking less likely, mainly because the EU will not allow that without the government accepting free movement of people.

Ironically the best option for farming, in theory, is trading on the basis of WTO tariffs. Because the UK is a huge net importer of food, this would increase farm gate prices for most commodities, because imports would be much more expensive. The exception is lamb, which depends on exports.

However there is a huge 'but' with this, which needs to be lit up in large letters, before farmers conclude this is the best option. It is impossible to believe that the government would allow an outcome that would drive a massive rise in prices for consumers. This would be seen as evidence that Brexit has failed.

This means we are back to there being no real trade or support plan for agriculture – and no evidence of one emerging any time soon, as negotiations on trade are pushed further down the road by Brussels.