Brexit has already had some significant effects on East Anglia's farming industry - but the biggest impacts are yet to come in a subsidy-free era of global free trade.

There was a collective sigh of relief from the region's agricultural community when an EU trade deal was struck at the end of last year, meaning the transition period ended on December 31 without the worst-case "no deal" scenario.

But six months on, it is clear that free trade is not as frictionless as they had hoped.

In the first quarter of 2021, the Food and Drink Exporters Association says food and drink exports to the EU fell by 55pc, compared to 2019 figures - a more realistic baseline comparison than the pandemic-hit 2020.

Analysts said it is unclear how much of that decrease is related to the Covid pandemic, but Brexit factors include costly additional veterinary certificates and border controls for dairy and meat products, an export ban on seed potatoes from the UK, and the end of exports of live animals, including high-value breeding livestock, due to a lack of border control posts in Europe.

There have also been delays and price hikes for imported machinery parts and raw materials, while horticultural growers bringing "high risk" plants from abroad have been hit with a raft of new import certificates and inspections.

Meanwhile, the end of free movement has exacerbated growing fears over an "acute" shortage of seasonal migrant workers to pick and pack fruit and vegetables throughout the summer.

Those concerns have also spread into ancillary industries, with a lack of HGV drivers sparking emergency meetings between government, retailers and logistics groups this week.

But the most fundamental long-term impacts of Brexit are still to come.

Chief among them is the end of the EU's system of "direct payment" subsidies - a large proportion of income for many farms - which will be phased out over the next seven years, to be replaced with a new system of environmental payments, still under development.

That has sparked serious questions over how an increasingly environmentally-focused industry can compete against less-regulated farmers producing cheap food to lower standards in other countries that are about to become our post-Brexit trade partners.

Gary Ford, East Anglia regional adviser for the National Farmers' Union (NFU), said the recent trade deal agreed with Australia highlighted those longer-term concerns.

"That is a source of intense frustration and understandable anger," he said. "We have got among the highest environmental and animal welfare standards in the world, but we know there are different standards operating in countries that we are about to enter into trade deals with.

"We are all for free trade agreements, because they do open opportunities for UK farmers. But it has got to be fair trade. There have got to be safeguards, and there has to be a level playing field."

Mr Ford said it was difficult to attribute the changes of the last six months to either Covid or Brexit - but together they represented a "perfect storm".

"The much-trumpeted deal with the EU was not quite what we were promised," he said. "We avoided the 'cliff edge' and everybody was hugely relieved but then the detail started to come and we started to see the friction and the bureaucracy and the additional cost of exporting to the EU.

"One of the big things at the moment is the availability of labour, not only in the horticulture sector but also in the supply chain. We are very reliant on seasonal labour in particular, but what I am hearing from farmers is that it is really starting to bite, and starting to affect their business.

"When it comes to the agricultural transition plan, and moving away from direct payment subsidies to 'public money for public goods' we know the pain at the moment but we don't know the gain.

We know the subsidies will be phased out over the next seven years but we don't know much about the Sustainable Farming Incentive (part of the replacement environmental scheme). That uncertainty is not helping farm business to plan going forward, so we desperately need some clarity.

"But I am optimistic. Agriculture in East Anglia is extremely resilient and we have some superb, efficient and innovative farmers in Norfolk and Suffolk, along with some world-class agri-businesses. We are only 62pc self-sufficient and we have 65m consumers on our doorstep, so there will be opportunities for them to supply more of our own market going forward."

Gail Soutar, chief EU exit and international trade adviser for the NFU, said while subsidy losses, labour shortages and trade competitiveness were longer-term concerns, the most pronounced effect of Brexit so far had been the establishment of trade barriers with the EU - although this had been felt more keenly by food processors and wholesalers than farmers themselves.

"The strange thing is, you would expect that to result in over-supply and price collapse for farmers, but we've seen prices stay quite high, which has been really positive," she said.

"That is because under Covid people are buying more locally, and because hospitality has been closed the vast majority of what we are consuming is coming from supermarkets, which tend to have very good British sourcing policies.

"The concerns we have is what is going to happen in the next quarter when things start to get back to more like normal, with hospitality opening and imports coming back to a level more like normality. If you are not getting so many exports away, it could start to have an impact on prices. But so far, from a farmers perspective, they have not seen large-scale disruption to prices as a result of Brexit."