Supermarkets Morrisons and Waitrose have began to limit the amount of cooking oil customers can buy due to shortages sparked by the war in Ukraine.
Both supermarkets have limited bottles of cooking oil to two per customer.
The rationing is because the Russian war in Ukraine has affected the production of sunflower oil.
Ukraine is the world's biggest producer of sunflower oil, accounting for around half of global supplies.
Russia produces slightly less, but the two countries together make around 80% of all sunflower oil.
The war means shortages of sunflower oil and in turn shoppers are buying other cooking oils instead, so now Waitrose and Morrisons have introduced limits on all oils.
Both supermarkets have been putting up signs in stores to let customers know of the new rules.
A Waitrose spokesperson said: "We want to ensure customers continue to have a choice of cooking oil so we are asking them to buy no more than two units each."
Morrisons has brought in the same rule, The Express reports - with the same restrictions apply to customers shopping online.
Morrisons has been approached for comment.
Around 50% of sunflower oil used by fish and chip shops comes from Ukraine, leading to fears the price of the takeaway food will go up.
The shortage is also threatening supplies of Ireland's favourite snack, Tayto crisps.
The UK grows enough oilseeds for 80% of our needs, but has to import the rest.
Russia is also the world's second-biggest producer of crude oil.
It supplies a third of Europe's oil, raising fears that supplies could be limited due to the conflict with Ukraine.
Rises in oil prices will increase the cost of farming and harvesting food, as well as transporting it to shops.
The cost of milk could soon rise by more than 50%, experts warn - meaning Brits could soon pay 80p not 60p for a pint.
A 'tsunami' of rising farming costs has been blamed for this, with experts listing steep increases in fuel, fertiliser and animal feed.
Much of this is due to the ongoing war started by Russia against Ukraine.
The upshot is that the price of four pints of milk could rise from £1.15 to between £1.60-£1.70, according to UK's dairy adviser Kite Consulting.
A typical pack of butter could increase from £1.55 to more than £2.
