Tomatoes are in short supply on supermarket shelves due to bad weather in Europe and Africa.
The UK relies on countries such as Morocco and Spain for tomatoes during the winter.
But in Morocco, growers have struggled with cold weather, heavy rain and floods.
Suppliers have been hit by ferry cancellations, which have affected lorry transport.
Spanish crops have also been affected by bad weather in the past three or four weeks.
Andrew Opie, director of food and sustainability at the British Retail Consortium, which represents UK supermarkets, said: “Difficult weather conditions in the south of Europe and northern Africa have disrupted harvest for some fruit and vegetables including tomatoes.
“However, supermarkets are adept at managing supply chain issues and are working with farmers to ensure that customers are able to access a wide range of fresh produce.”
Last year, Britain’s supermarkets suffered from supply chain disruptions after Russia’s invasion of Ukraine, although the situation improved as Christmas drew nearer.
‘We should never take our food security for granted’
It comes as the National Farmers’ Union president Minette Batters is expected to warn that time is running out for the government to back British farming.
Delivering the opening address at the union’s annual conference, she will say: “As the global population continues to rise, and parts of the planet become less suited to producing the food we eat, we have an opportunity, and a duty, to get the best out of our maritime climate.
“Secondly, in the face of climate change, we should be unwavering in our commitment to achieving net zero and contributing to our energy security through on-farm renewables generation.
“And thirdly, we should never take our food security for granted.
“But the fact remains, volatility, uncertainty and instability are the greatest risks to farm businesses in England and Wales today.
“Critically, those consequences will be felt far beyond farming, they will be felt across the natural environment, and in struggling households across the country.”
Ms Batters will add: “More often than not – it has been incredibly hard getting government to back up its rhetoric with concrete actions.
“The time is nearly up for government to demonstrate its commitment to food and farming in our great country, not just by saying they support us, but by showing us they do.
“I won’t let the opposition off the hook either – I believe the rural vote will be crucial in the next election.”