British food security is being hit by a double whammy of climate change impacts at home and in the countries it imports products from, analysis warns.

Key crops from potatoes and onions to wheat and sugar are being hit by damaging heat, drought and floods around the world, pushing up prices and threatening food security, an assessment from think tank the Energy and Climate Intelligence Unit (ECIU) says.

But while it “is tempting” to suggest that the UK should increase domestic production to make up for poor harvests abroad, Britain too is struggling in the face of climate impacts, the organisation said.

Its analysis highlights the UK imports around half the food we eat, with around half of that made up of commodities we cannot grown here, including cocoa, bananas and coffee.

But many foods are produced in the UK, at least seasonally in some cases, with British produce including rapeseed for cooking oil, onions, sugar, cauliflowers, broccoli, wheat and potatoes.

But we also rely on imports for those crops from areas such as the Mediterranean and western Europe, and both home and abroad, agriculture is being hit by climate impacts.

For example, the UK is 47% self-sufficient in onions, but this year’s wet winter, which scientists have said saw rain made 20% heavier by climate change, prevented or delayed planting of onion crops, the analysis said.

At the same time, nearly two-fifths of onion imports come from Mediterranean regions which have been experiencing severe and prolonged drought which scientists say is virtually impossible without climate change, hitting crops.

Similarly, for cooking oils, UK oilseed rape crops are projected to be as much as 38% lower this year due to the wet weather this winter and early spring, while Mediterranean olive harvests have been hit by extreme heat in the past two years.

Broccoli and cauliflowers – for which we are 55% self sufficient – have been hit by the wet weather in the UK and by the extreme heat and dry conditions in the Mediterranean, with top supplier Spain seeing historic drought since the start of 2024, the analysis said.

Extreme heat and drought hit key sugarcane producers India and Thailand in 2023 and 2024, pushing up global prices for sugar, increasing the cost for British consumers by 68% over the last two years.

Wheat and potatoes have been hit by wet weather domestically, while key wheat suppliers such as France and Germany have also suffered heavy rainfall in the past year, while Egypt, which produces potatoes for UK markets, is struggling with extreme heat.

ECIU also warned that volatile oil and gas prices have added to the problem, for example making it too expensive for some producers to grow tomatoes in heated greenhouses in the UK.

The organisation called for cuts to greenhouse gas emissions to curb climate change, as well as support for farmers adapting to the changing conditions, which are already being seen at 1.2C of global warming and will worsen as temperatures continue to rise.

Gareth Redmond-King, head of international programme at ECIU, said British consumers had seen average food bills go up by at least £360 over the last two years as a result of climate-driven extremes hitting harvests.

“We import half of what we eat, and it’s tempting to suggest we can simply grow more at home as heat, drought, fire and flood hit food production in too many parts of the world.

“But the UK had its wettest winter on record this year, with devastating effects for farmers trying to get food crops planted – made worse by a wet spring threatening delayed harvests.

“The end result is our food security is at risk, with prices of staples that we grow at home and import both pushed up by shortages.”

He said the only solution to avert “ever worse extremes” was to reach net zero emissions, while farmers needed help to adapt food production to temperature rises already baked in.

In the UK, new farming support schemes could help by incentivising improved soil health and the planting of more hedgerows and trees that protect land from flooding, while in developing countries climate finance was needed to help future-proof farming against heat and drought, he said.