The chairman of Britain’s biggest supermarket chain has warned that “the worst is yet to come” on food price inflation, as he predicted it will soon hit 5%.

John Allan, who has chaired Tesco since 2015, told the BBC’s Sunday Morning programme that he was well aware people on very tight budgets were having to choose between food and heating. He said the idea that this was happening was very troubling.

Overall inflation currently stands at 5.4%, a 30-year high, and is predicted to top 6% in the spring, just one element of the cost of living crisis facing UK households. Poverty groups have warned about the impending threat to those on the lowest incomes.

“In some ways the worst is still to come – because although food price inflation in Tesco last quarter was only 1%, we are impacted by rising energy prices. Our suppliers are impacted by rising energy prices. We’re doing all we can to offset it … but that’s the sort of number we’re talking about. Of course, 5%,” he said.

Allan admitted some people would “of course” have less to spend on luxuries, as the price hikes coincide with a rise in national insurance contributions and the £693 increase in the average family’s annual energy bill, to £1,971, both of which come into effect in April.

About a fifth of the fresh food the UK imports comes from areas threatened with climate chaos, putting people’s health and diets at risk, MPs have found.

The environmental audit committee called on ministers to set out a clear plan for how the UK’s food supplies could be protected from the climate emergency and to publish information on how food may be affected by Brexit.

Currently, 40% of the UK’s food is imported, according to the report published on Tuesday. In the very near future, people would be at risk from sudden lurches in food prices if a no-deal Brexit resulted in trouble with imports, including higher costs, delays and shortages.

Mary Creagh, the chair of the committee, said: “We are facing a food security crisis, exacerbated by uncertainty over the UK’s future trading position with the EU and the rest of the world. Ministers must now publish all the information they hold from Operation Yellowhammer on food security and likely costs in the event of a no-deal Brexit.”

Beyond the immediate effects of Brexit, the climate emergency and changing trade relationships may put the British diet in jeopardy. The MPs called for a national food council that would cover food production, nutrition and public health issues, and for stringent annual targets to reduce the UK’s high levels of food waste.

Water consumption across the UK should be set at 100 litres (22 gallons) per person per day, the MPs found. This would require changes to water availability and potentially to metering. Sustainable cities should also be made more resilient to the effects of the climate crisis, and town planners should be more involved in improving the design of cities to reduce greenhouse gas emissions, for instance through more efficient transport networks.

The cost of a family’s weekly shop could rocket by more than £800 a year if the UK leaves the EU without a deal, a major union has warned.

Analysis for the GMB found that the bill for a typical supermarket basket of goods would increase by £15.61 a week – 17 per cent – if Britain was forced to fall back on World Trade Organisation rules, which require tariffs on many goods.

Under the WTO’s “most favoured nation” rules, the price of a 250g pack of butter would rise by 42p (up 28 per cent). Other increases would include 62p for a 460g block of cheddar(up 29 per cent), 43p for a pack of eight sausages (up 25 per cent), 32p for 2.5kg of potatoes (up 14 per cent) and £2.56 for a bottle of red wine (up 32 per cent), according to Acuity Analysis

The government is expected next week to spell out its plan to mitigate a potential £9bn food-price shock from a no-deal Brexit, as analysts predict the cost of staples such as beef, cheddar cheese and tomatoes could soar.

With just over a month until the Brexit deadline, the Department for International Trade is expected on Monday to publish a list of new import taxes, or tariffs, that will apply to 5,200 products, including food and clothing, should the UK crash out of the EU without a deal.

The relationship with the EU is key to the price of food because nearly one third of the food eaten in the UK comes from the bloc. At this time of year the situation is more acute because, with UK produce out of season, 90% of lettuces, 80% of tomatoes and 70% of soft fruit is sourced from, or via, the EU.

 “Food and drink tariff rates will be higher than those in any other supply chain,” says Richard Lim, chief executive of consultancy firm Retail Economics. “All stages within the food supply chain will experience increased costs, with retailers hit disproportionately as processed goods attract higher duties than raw materials and semi-processed goods.”

In 2017 the UK bought about £34bn of groceries from the EU, which arrived on supermarket shelves and at factory gates without being hit by customs duties or other trade costs. But if the UK leaves the EU without a deal, both will fall back on the World Trade Organisation’s “most favoured nation” tariffs, which means they must pay import duties on each other’s trade.

On that basis the UK’s 2017 EU food imports would come with a hefty £9.3bn tariff bill on top, according to Retail Economics’s analysis.

Grocery prices fell 0.8% in June, extending May’s 0.3% fall and marking the deepest deflation in food for over a year, according to the British Retail Consortium-Nielsen Shop Price Index.

Shop prices overall, including non-food items, fell 2% year-on-year, marking the 38th consecutive month of decline.

The BRC said it was an “extraordinary run of deflation”.

However, the retail trade body said it eventually expected prices to rise again.

“The time it takes for any price increases to make a reappearance will depend on a combination of factors including the future value of the pound, commodity prices and any eventual impact of the Brexit vote on input costs,” said BRC chief executive Helen Dickinson.

The shop price index reflects the period ahead of the referendum vote from 6 to 10 June.

The sharp fall in the pound, which has plunged about 11% against the US dollar since the outcome of the EU referendum vote, has led several analysts to warn that the price of groceries could rise longer term.

Some 40% of food consumed in the UK is imported meaning any long-term shift in exchange rates could lead to higher food costs.

It explains – “Overall, shop prices climbed 2.3pc in the past year, according to the monthly index from the trade body and researchers Nielsen, down from 2.5pc in April. However, food prices rose at more than double that rate – 4.9pc in the year to May, marking a pick-up in pace from the 4.7pc rate seen the previous month.

“Recent volatility in the cost of key commodities, linked to dry weather and global demand, is now working through to the shop price of some food,” said Stephen Robertson, the BRC’s director general.

“Disappointing crops and demand from the biofuel industry have helped corn prices rise 112pc in an year and wheat 72pc.”

I know first tier authorities with their responsibilities around adult social care will be concerned  from a statutory point of view about this but I wonder what District Councils and the Voluntary and Community sector might do to help tackle the worst effects of it on their residents?