Food inflation pushed up UK grocery sales in the 12 weeks to 8 August, according to the latest data from analysts at Kantar Worldpanel.

Food prices rose 2.2% over the 12-week period, Kantar said, helping the country’s grocery sector grow by 4.5%.

The latest UK inflation data, also issued today (17 August), showed that food prices – when measured under the Consumer Prices Index – rose by 0.7% between June and July. Higher prices for fish, milk, cheese, eggs and vegetables drove the increase.

The increase in food prices comes amid growing concerns about the price of commodities but Kantar said the upward pressure on prices was due to other factors.

“This increase is caused by the end of World Cup-related alcohol promotions and a comparison with falling prices a year ago rather than sharp commodity price increases which have featured in recent news items,” Kantar said.

Reflecting on the relative performance of the UK’s big four food retailers, Kantar said Sainsbury’s and Morrisons had gained share, while Tesco and Asda saw their market share eroded.

“Morrisons in particular has shown a strong performance this month,” said Kantar communications director Ed Garner. “Despite some commentators expecting the Morrisons growth to run out of steam it still comfortably leads the top four in terms of year-on-year performance with growth of 6.9%.”

Sainsbury’s, the UK’s number three retailer, saw its sales rise 5.9%. Asda, the country’s second-largest retailer, grew sales by 2.9%. Tesco’s sales were up 3.9%.