Supermarket prices surged at the fastest pace for more than a year in October amid supply chain disruption and lorry driver shortages, new figures have shown.
The latest data from Kantar revealed that like-for-like grocery inflation rose to 2.1% in October - the highest since August last year.
Kantar said prices were rising fastest in savoury snacks, canned cola drinks and crisps.
It comes as supply chain issues in the UK and globally continue to push prices up across the board, with the Bank of England warning last week that inflation will rocket to its highest level for 10 years.
Retailers are resorting to price hikes to offset higher costs of transport, fuel, energy, stock and wages, which is seeing the cost of living rise sharply.
The disruption has also been leading to shortages of some products in recent months.
The Kantar figures also showed another fall in supermarket sales, down 1.9% in the quarter to October 31 as shopper habits begin to settle after last year's pandemic boost.
It said the trend for fewer but bigger trips to stores looked set to stay, with shoppers still making 40 million fewer trips to supermarkets per month than in 2019.
But sales remained 7.3% higher than in 2019 before the pandemic struck.
Fraser McKevitt, head of retail and consumer insight at Kantar, said: "Grocery prices are rising and this month inflation hit its highest rate since August 2020, when retailers were still cutting promotions to maintain stock on the shelves.
"As prices increase in certain categories, we can expect shoppers to continue to visit several supermarkets and shop around to find the best deals.
"Already, households visit an average of 3.3 supermarkets per month in order to find the best value for money."
Online sales also levelled out in the most recent quarter, accounting for 12.4% of total the grocery market for the second month in a row.
Mr McKevitt said a fifth of households were consistently ordering their groceries online every month, becoming "long-term converts" even after restrictions have lifted.
There was also a return to "bigger and better celebrations" this year, with Halloween festivities driving sales of pumpkins up 26% and seasonal sweet sales up 27% last month, according to Kantar.
As Christmas ads also picked up in earnest, Britons began stocking up on festive items, with frozen poultry sales up 27% year-on-year and 4.7 million households already buying mince pies.
The data showed Tesco was the only one of the so-called Big Four chains to increase its market share in the quarter, at 27.6% against 27% a year ago thanks to a 0.3% rise in sales.
Sainsbury's saw its share slip to 15.2% from 15.3%, wits Asda's dropping to 14.3% from 14.4% and Morrisons' falling to 10% from 10.2%.
