Why did inflation unexpectedly rise last month?

Inflation rose unexpectedly last month, defying economic forecasts.

The latest data from the Office for National Statistics (ONS) showed a rise in the Consumer Prices Index (CPI) in February, up to 10.4% from 10.1% in January. Most economists were expecting CPI to fall to 9.9% in February.

It comes after three straight months of declining inflation, which had seen hopes mount that the worst of the crisis was behind us and that the era of double-digit inflation was coming to an end. So what exactly has contributed to the unexpected increase - and should we be worried that the cost crisis is ramping up again?

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The surprise jump in inflation comes after food and non-alcoholic drinks prices rose by 18% year-on-year last month, up from 16.7% in January and the highest since August 1977. Meanwhile inflation overall in restaurants and cafes stood at 11.4% last month, up from 9.4% in January and the highest since December 1991.

Food prices also leapt up by 18.3% year-on-year in February, driven largely by the salad and vegetable shortages seen across supermarkets in recent weeks. Tomatoes, peppers and cucumbers were some of the vegetables impacted, with retailers saying a combination of bad weather and related transport problems in north Africa and Europe were causing significant supply problems.

The ONS said the rate of vegetable price inflation alone jumped to 18%, its highest level for 14 years.

The latest data also showed rises in the CPI measure of inflation including housing costs (CPIH), up to 9.2% in February from 8.8% in January, while the Retail Prices Index (RPI) leaped to 13.8% from 13.4% in January. ONS chief