Cereal giant Kellogg's has again been told to withdraw two television advertisements because they are deemed to be marketing unhealthy food to children.

The Advertising Standards Board (ABS) upheld a complaint from advocacy group Obesity Policy Coalition regarding Kellogg's recent "fun facts" advertisements.

The board found two versions of those advertisements featuring animated dinosaurs, snails and children's voices, were directed primarily to children.

They were in breach of the Responsible Children's Marketing Initiative (RCMI), the board said.

It is the second time in two weeks that the board has upheld a complaint from the Obesity Policy Coalition about a Kellogg's advertisement.

Call to monitor animation in food ads

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 3 minutes 50 seconds 3 m 50 s 'Cereal' offender: Kellogg's TV ads pulled by advertising watchdog ( Alison Caldwell ) Download 1.8 MB

The coalition's spokeswoman Jane Martin says the board's decision shows a recognition that using animations are not appropriate when advertising junk food.

"We know that these types of advertisements are very powerful and influential with children and using the kinds of themes that they did, it's good that this has been recognised."

She says the decisions demonstrate that the self regulation of junk food advertising doesn't work and hoped the wasted cost would deter other companies.

"Obviously these advertisements won't be able to be run any more, it's a big cost to them," she said.

"Children should be protected from this kind of marketing, they do have a vulnerability, they can't distinguish between entertainment and advertising."

She says all major public health groups in Australia recognised the need to protect children.

If the industry was not able to stick to regulations set up, then she called upon government agencies to intervene.

"What we need to do is call time on self regulation, this has been in place for four years and industry still aren't managing to abide by the rules that they set up, they're still marking their own homework," Ms Martin said.

"It's time that government stepped in and regulated unhealthy food marketing to children."

Ads undermining schools' efforts

In addition, she said advertisers who are abiding by the rules are let down.

"The only advertisers who are doing the right thing, they're now disadvantaged," she said. "It's industry's regulation and industry should stick to it."

Kellogg's said in a statement that it did not know of any consumer complaints about the ads.

"As with the Coco Pops advertisement, the ASB didn't receive any complaints from consumers about this LCMs advertisement, but just the one from a lobby group.

"Nonetheless we fully respect and accept the role of the ASB and its decision."

Anti-obesity calls have been growing around the globe, including New York mayor Michael Bloomberg moving to ban large soft drinks and calls in Britain to ban high-sugar cereals including Coco Pops.

Chefs such as Jamie Oliver have long been calling for and installing healthier lunches in schools in Britain and the United States.

Ms Martin says advertisements such as the banned Kellogg's ones reduced schools' and parents urging healthier foods.

"We know children's diets are very poor, we've got 25 per cent of children overweight and obese," she said.

"It's undermining the other efforts of schools and parents to try and encourage healthy eating in their children."