While people are beginning to cut back on the amount of salt they add to their food or use in cooking, manufacturers are not doing enough to reduce the content of their products, according to a report from Food Standards Agency.

Industry chiefs have said they have already gone as far as they can in lowering salt levels, claiming that further reductions would affect taste and drive away customers.

But the FSA has challenged the industry to cut the salt content of processed products still further, setting a potential collision course between the Government and manufacturers.

Men currently eat an average of 11g and women 8g of salt a day. The Government has set a target of reducing intake to 6g a day within the next five years.

High levels of salt consumption are linked to heart disease, stroke and diabetes - the biggest killers in Britain. One in four people eats a ready meal at least once a week and three-quarters of daily salt intake comes from processed food, according to the FSA report.

Nearly half - 46 per cent of people - say they are trying to cut down on their salt intake since the FSA launched a high-profile campaign on the issue last year.

Sales of table salt have fallen by 10 per cent in the past 12 months, but only a third of adults look at the labels to check the salt content when buying processed food.

Deirdre Hutton, chair of the FSA, said: "It is a great first step that so many people now know that too much salt is bad for them and are cutting down on the amount they add to food.

"In the past year, more food companies have started to reduce the amount of salt in processed foods, but we need more of them to do the same if we are to reach our goal of reducing the UK's salt consumption to 6g by 2010."

While some food manufacturers, such as Unilever, whose brands include Birds Eye, and Heinz have made substantial reductions in salt levels, others have been reluctant to follow suit.

Burger King has pulled out of the joint initiative between the FSA and the industry to re-formulate the content of processed foods.

The company says it has no plans to further reduce levels of salt, fat and sugar in its products after making earlier concessions.

Earlier this month, the Food and Drink Federation, which represents manufacturers, issued a report detailing how the industry had worked to reduce salt levels in many products.

But leading companies warned that further reductions may not be possible because the resulting lack of taste in foods would put customers off.

The supermarket giant Tesco has reduced the salt content in ready meals such as lasagne and chicken paella by more than 50 per cent.

Carolyn Bradley, commercial director of the company, said: "The challenge we face is to reduce salt and make Tesco products healthier, whilst continuing to meet customer expectations on taste, quality and price."

Peter Sherratt, of the Salt Manufacturers Association, said: "No one has yet proved that cutting salt produces any long-term health benefits for the general population. The Government should surely be investing our money in solutions that are known to work."

Manufacturers are coming under increasing pressure to make their brands more healthy, as the FSA is still considering whether to impose "signposting" labels on all foods to tell consumers how healthy they are.

The industry is opposed to the idea, saying it is too simplistic.

Ministers are also considering whether to ban advertising of junk food on television before the 9pm watershed.