Snacks sold in schools will have to cut the fat, sugar and salt under the latest crackdown on junk food won by former President Clinton.

Just five months after a similar agreement targeting the sale of sodas in schools, Clinton and the American Heart Association announced a deal Friday with several major food companies to make school snacks healthier — the latest assault on the nation's childhood obesity epidemic.

"By working with schools and industry to implement these guidelines, we are helping to give parents peace of mind that their kids will be able to make healthier choices at school," said Dr. Raymond Gibbons, president of the heart association.

The agreement with Kraft Foods Inc., Mars Inc., Campbell Soup Co., Groupe Danone SA and PepsiCo Inc. sets guidelines for fat, sugar, sodium and calories for snack foods sold in school vending machines, stores and snack bars. Those companies make everything from M&M's, yogurt and granola bars to Frito-Lay potato chips, Snickers bars and canned soups.

Under the guidelines, most foods won't be permitted to derive more than 35 percent of their calories from fat and more than 10 percent from saturated fat. There will be a limit of 35 percent for sugar content by weight.

An example of a snack that would be banned is a Snickers bar, which has 280 calories, 130 of them from fat. The candy bar has 30 grams of sugar out of 58.7 total grams.

Gibbons said Thursday the guidelines are based on the recommendations of leading scientists "as to what we should be doing to provide more nutritious foods for our kids."

Charles Nicolas, a spokesman for PepsiCo, which owns Frito-Lay and Quaker, said Frito-Lay already has products that meet the guidelines, such as baked potato chips and reduced-sugar chewy bars.

"We're going to change a few recipes so that more snacks meet those guidelines as well," he said.

Kraft said in a statement that it would add the sodium and calorie caps to its nutrition guidelines "and extend these guidelines to include all of our competitive foods sold in schools."

The William J. Clinton Foundation teamed up with the heart association to form the Alliance for a Healthier Generation in 2005. The alliance was formed to combat childhood obesity, which has been blamed for an increase in early-onset diabetes and other ills.

In May, the alliance announced an agreement with beverage industry leaders to sell only water, unsweetened juice and low-fat and nonfat milk in elementary and middle schools. Diet sodas and sports drinks are still being sold in high schools.

Officials said that agreement covered 87 percent of the soft drink market in public and private schools.

Bob Harrison, executive director of the alliance, said the snack-food industry is not as concentrated as the beverage industry, so the reach of this agreement will not be as wide as the earlier one.

But he said the five companies participating in the new agreement are market leaders and their influence will be felt.