Promotions accounted for a bigger share of supermarket sales in April than ever before, according to exclusive data from Nielsen.

Almost a third (32%) of sales at the big four came from promotional offers in the four weeks to 18 April, beating the previous record of 31% last Christmas. This is the first time Easter offers have topped Christmas activity. Last April, the share of promotional sales peaked at 28%, compared with 29% at Christmas.

The high suggests the promotional frenzy of recent months is set to continue. In previous years, activity generally tailed off in the months following Easter, peaking again in August in a promotional drive traditionally much bigger than that of Easter.

"It is clear from this research that shoppers are increasingly looking to make savings on their grocery bills and they will continue to respond to promotions," said senior retailer services manager Mike Watkins. "We can expect this trend to intensify for the rest of 2009 and can expect further competition from the multiples and the discounters."

The soaring promotional activity has helped allay consumers' fears about rising food prices, Nielsen added. In October 2008, more than 25% of Nielsen's respondents cited food price inflation as a major worry, but this fell to 13% in the latest study.

However, other signs from the survey are less positive for heavy promoters - customers said they were trying to avoid promotional offers as part of their effort to control supermarket spend, suggesting the swathe of offers could be fuelled more by retailers and manufacturers than consumer pressure.