A survey of 20 of the leading food and drink manufacturers has shown that 36% of processed foods will have less salt by the end of this year in response to pressure from government and consumers.

The Food and Drink Federation said it had conducted the survey to show that it could change without further regulation. It warned that it could not go further without making its products unpalatable to consumers. Campaign groups said the changes were still too little and too late.

Heinz said it now uses 19% less salt in manufacturing than a year ago, with its baked beans containing 14% less. Kellogg's brought in a 25% reduced salt recipe for Corn Flakes. Pepsico International cut salt levels in Oat Crunchies by 33% and reduced sugar levels in Sugar Puffs by 25%.

Graham MacGregor, professor of cardiovascular medicine and chairman of the campaign group Consensus Action on Salt and Health (CASH), welcomed the reduction but added: "Only just over a third of products have less salt added to them than they did in 2004.

"The food industry is responsible for adding this salt to our food and it must also take responsibility for removing it. We need to see 40% or more of the salt in our food being reduced. This report doesn't tell us how or when this will happen."

The survey also shows most leading manufacturers plan to put more nutritional information on the back of packs by the end of 2006. The campaign group the Food Commission dismissed this as an effort to avoid simpler colour-coded labelling on the front of packs.

"It has taken enormous pressure and public embarrassment to get the industry to change on salt. We hope it won't take so long to move on fat, sugar and genuinely helpful labelling," Kath Dalmeny, of the Food Commission, said. The view was echoed by the National Consumer Council. "It's a welcome start but there's a long way to go," director Ed Mayo said.