The food industry has hit back at ministers who accused it of failing to take real action on the healthiness of its products.

Health minister Melanie Johnson went public with her criticisms of a failure to reduce the salt content in food on Thursday.

Off-the-record briefing was also used to promise "tough" government action if producers did not begin to make efforts on their own.

But an open letter from a range of business and farming representatives on Friday slammed "inept political spin" and defended the industry's record.

"Over the last two years our industries have worked closely and constructively with the Food Standards Agency, and latterly with the Department of Health, both on a sector and individual company basis, to produce both plans for and actual substantial salt reductions," it said.

"This work will continue, but is not helped by inept political spin which has nothing to do with real attempts to improve the nation's health."

The letter was signed by Kevin Hawkins, director general of the British Retail Consortium, Bob Cotton, chief executive of the British Hospitality Association, Sylvia Jay, director general of the Food and Drink Federation, and Richard Macdonald, director general of the National Farmers' Union.

High salt levels have been proven to lead to greater incidences of heart attacks and stroke, while obesity has also become a hot political issue in recent months.

Ministers want to crackdown on the content of pre-packaged foods such as pizzas, ready meals and breakfast cereals.

But they have so far shied away from severe action such as levying a tax on salty or fatty foods or even compulsory cigarette-style health warnings.