Ofcom has stood by its decision to extend its "junk" food TV advertising restrictions to include all children under the age of 16 - however broadcasters and advertisers have been given a year before it comes into force.

Ofcom has opted for a "phased introduction" of the restrictions on the basis that the original consultation plans advertisers and broadcasters had prepared for, focused on scheduling restrictions for under-10s only.

The introduction of "junk" food TV advertising restrictions for under-10s will come into force from the 1 April.

Children's channels will be allowed a graduated phase-in period, with full implementation required by the end of December 2008.

Last November Ofcom surprised the advertising and broadcasting industry when it announced that - in addition to a total ban on junk food advertising around all children's programming and on all children's channels - the restrictions would be extended to all programmes that have a "particular appeal" to under-16s regardless of when it airs on TV.

It had previously focussed on restrictions to the under-10s during particular time periods.

This brought into the ban a range of programmes previously considered to be unaffected by the proposals such as, potentially, The Simpsons, Hollyoaks, The X Factor, Lost, Friends and popular music shows.

The most high profile channels likely to be affected will be Sky One and Sky Two.

Ofcom has introduced an index that broadcasters will have to use to assess audience levels on each show and those that have a 20% higher proportion of under-16 viewers that the UK average will not be allowed to carry junk food ads.

New rules governing the content of new TV ads - which applies to all food and drink advertising to under 12s irrespective of when it is scheduled - comes into force immediately for new ad campaigns.

Content rules include a ban on using celebrities who appeal to young people and on licensed characters - but not manufacturers' own characters such as Frosties' Tony the Tiger.

Existing advertising campaigns or those in the final stages of creative execution can be broadcast until the end of June 2007.

However, from 1 July 2007 all advertising campaigns must comply with the new content rules.

Ofcom has based its definition of what constitutes "junk" food on a nutrient profiling system developed by the Food Standards Agency that identifies foods high in fat, salt and sugar.

Ofcom will review the effectiveness and scope of new restrictions in autumn 2008, one year after the full implementation of the new content rules.

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