Mr Kipling cakes owner Premier Foods is raising prices amid a cost of living crisis pushing up household food bills.
The group - which also owns brands such as Oxo cubes, Sharwoods and Ambrosia - said the Ukraine war was pushing up prices of many of its ingredients, including wheat and dairy, while fuel and energy costs are also rocketing.
The UK rate of inflation has soared to 9% - a new 40-year high - as the cost of living continues to spiral.
The 9% inflation figure for the 12 months to April marks one of the highest one-year increases in consumer prices since records began in 1989.
The Consumer Prices Index (CPI) measure of inflation had stood at 7% in March, according to data from the Office for National Statistics (ONS).
This is up from 7% in the previous month. The Bank of England has already predicted that inflation could rise above 10% this year.
CPI shows how much the price of goods and services has risen or fallen over time.
For example, if something that cost £1 a year ago now costs £1.02 today, that rate of inflation would be 2%.
Six everyday things that have gone up in price
The ONS notes how the cost of energy was the largest price rise last month. It comes after the Ofgem price cap was hiked by hundreds of pounds on April 1 .
For those on a variable energy bill tariff who pay by direct debit, the price cap has risen by £693 from £1,277 to £1,971.
Prepayment customers have been hit by a bigger jump, with their price cap going up by £708, from £1,309 to £2,017.
The highest prices on record for both petrol and diesel also contributed to rising inflation in April.
Here are the biggest price increases over the 12 months to April, according to the ONS:
- Natural gas - 95.5%
- Electricity - 53.5%
- Motor fuels - 31.4%
- Furniture and maintenance - 10.7%
- Restaurants and hotels - 8%
- Food and non-alcoholic drinks - 6.7%
ONS chief economist Grant Fitzner said of the latest data: "Inflation rose steeply in April, driven by the sharp climb in electricity and gas prices as the higher price cap came into effect.
"Around three-quarters of the increase in the annual rate this month came from utility bills."
