“What we will do is grow more [food] here and we’ll buy more from around the world”

That is what the transport secretary Chris Grayling said could happen if Britain leaves the EU without a trade deal. He was responding to claims  that a no-deal Brexit would see the cost of food go up by 22 per cent.

But is Mr Grayling being realistic? FactCheck takes a look.

How might a no-deal Brexit increase food costs?

A no-deal Brexit would mean both the UK and the EU would have to put up tariffs on the goods and services they import from each other in order to comply with World Trade Organisation (WTO) rules. This could have knock-on effects on the price of food for British consumers.

Increasing Britain’s food self-sufficiency is a “noble ambition”, but do we have enough time before Brexit?

Mr Grayling suggested that one way to avoid the cost of food going up would be to grow more in the UK. But leading food and environmental scientists are sceptical about whether that would be feasible on a mass scale in such a short time frame.

We spoke to Professor Sue Hartley, Director of the Environmental Sustainability Institute at York University.

She explained that at the moment, the UK only produces around 60 per cent of its own food – “increasing that figure is a sensible and important policy goal but there is clearly a long way to go”.

The picture’s even more stark when we consider fresh fruit and vegetables – only 18 per cent of what we consume is grown in the UK.

She identified three key questions that would need to be resolved for Mr Grayling’s proposals to become feasible.

First of all, she asks “can we grow what we want to eat?”. In other words, would UK consumers have to accept a narrower range of options, depending on what we can grow in Britain?

Then we have the question of “where can we grow it?”. Given “the need for our limited land to provide multiple functions”, Professor Hartley asks “whose housing development would be cancelled, or what road expansion would be scrapped?”.

She suggests that alleviating this pressure will require major changes in our agricultural system, such as reduced meat consumption, to allow more people to be fed from the same area of land.

And finally: “who is going to grow it?”. Farming is an ageing profession: “a third of farmer owners are over 65” and there are growing skills shortages in key sectors, such as dairy. Indeed, many parts of the UK agricultural sector, particularly horticulture, are “heavily reliant on EU workers”.

Answering these questions will take time, says Professor Hartley, and would be difficult to resolve by March 2019. This is something the government itself recognises as it aims to produce a 25 year Plan for Food and Farming.

She says that the UK’s increasing reliance on imported food is something “we would need to address irrespective of Brexit”.

But the problem is time.

Professor Hartley concludes that becoming more self-sufficient is “a noble ambition and it’s something that should be in the government’s thinking – but it should have started with a clear vision for a national and regional UK food policy 20 years ago”.

Joint research by City University and the Universities of Sussex and Cardiff also casts doubt on whether Mr Grayling’s proposed course of action would be viable.

In a 2017 report “A Food Brexit: time to get real”, Professors Tim Lang, Erik Millstone and Terry Marsden say that “the implications of Brexit for food are potentially enormous”. They point out that “the UK food system, consumer tastes and prices have been thoroughly Europeanised. This would be impossible to cut out or back by March 2019 without enormous consequences”.

They warn that leaving the EU will be a “major disruptor of the current food system, which has undergone a transformation since 1945”. They say that the prospect of changing all this in two years “is bringing most food analysts and food industries out in a cold sweat”.

In particular, the reports authors are concerned about “volatile and/or rising food prices from a botched Food Brexit”, which they say “will hit the vulnerable even more”.

FactCheck verdict

Evidence from leading food and agriculture experts suggests that Chris Grayling’s proposal to “grow more” is desirable in the long term, but not feasible in the timeframe of a no-deal Brexit.

Analysts agree that the necessary changes would take decades, not years. With the UK’s departure from the EU scheduled for March 2019, there simply isn’t time to implement such major structural changes.

17 October 2017: We have amended this article to clarify that the head of Sainsbury’s was not the source of the claim that food prices would rise, as previously suggested.