Bosses at supermarket giant Sainbury's have doubled the price of bags to 20p, leaving punters furious.
Executives at the chain, the second largest in the UK, say the plan is aimed at reducing plastic use by the store.
It comes as part of a strategy to cut plastic use by more than 50% in five years, with the profits going to good causes, the company said.
But punters were left furious by the move, with some blasting the decision to hike prices as "daylight robbery and completely unacceptable".
Other eagle-eyed shoppers pointed out that Sainbury's rival Morrisons had recently started a similar initiative, and blamed the chain of attempting to cash in.
One angry punter tweeted : “Guessing they saw Morrisons get away with it and decided they wanted a bit of that action too!”
Another chipped in: “I get ‘saving the planet’. So offer a paper bag alternatively at 10p, stop profiteering from my forgetfulness!”
A third simply said: "daylight robbery and completely unacceptable".
In 2015 the Government introduced a law that put a 5p charge on plastic bags, leading Sainbury's and other supermarkets to cut single carrier bags completely.
These were then phased out and replaced with "bags for life", costing 10p each.
Back in August this year, Morrisons increased the price of its bags for life to 30p.
Meanwhile, Walmart giant ASDA hiked the price of its carrier bags from 9p to 15p.
Tesco , the UK's largest supermarket chain, has so far kept the cost of its bags at 10p.
Sainsbury's told The Sun: “We think 20p is fair. We’re really hoping it will help reduce our plastic usage.”
In September the supermarket giant removed plastic bags from its bakery, fruit and veg aisles and introduced a 30p drawstring carrier.
Sainsbury's, which has 186,900 employees, and owns a number of subsidiaries including Argos and Habitat, had revenues of £28.456 billion in 2018, according to the firm's annual report.