Ofcom is to allow advertisers to sponsor entire TV channels and radio stations for the first time.

For the past 15 years, advertisers have been allowed to sponsor individual radio and television programmes.

Ofcom now intends to amend the broadcasting code to expand sponsorship opportunities - subject to specific safeguards, such as preserving editorial independence and protecting under-18s.

The amendment follows a wide-ranging consultation by Ofcom in February on how channel sponsorship might be introduced.

Current programme sponsorship restrictions include news and current affairs shows and certain products, such as alcohol or gambling brands, sponsoring children's programming.

Ofcom's consultation looked at whether it would be appropriate to allow channels that broadcast some of these types of programmes to be sponsored at all.

The regulator's amendments to the code will allow the sponsorship of any channel, as long as that channel only shows a limited amount of programmes where sponsorship restrictions already apply.

The extending of sponsorship opportunities will be welcomed by broadcasters, who are set to lose advertising revenue when Ofcom announces the extent of the restrictions on junk food advertising next month.

David Fletcher, the head of research at Mediaedge:cia, says the extension of sponsorship rules will benefit channels with small audiences.

"With audience fragmentation, programmes on smaller channels can fail the "why bother?" test [because] the audience base is too small for advertisers to consider sponsorship - so channel sponsorship will allow a threshold audience size to be sponsored."

However, media agencies are uncertain how much channel sponsorship will benefit the major players such as ITV and Channel 4.

"It is content that is king more than the platform the programmes are provided on. Advertisers are after the Lost audience, not specifically Channel 4 or E4," said Darren Lucas, the television director at Initiative.

"The scale of the sponsorship and the diversity of the entire audience and programming on the big channels also makes it prohibitive to most advertisers.

"Digitally you can create advertiser channels such as the Audi Channel, Honda's offering or Orange's radio station, The Core."

Specific safeguards will be put in place by Ofcom to preserve editorial integrity and protect children.

For example, viewers must be made aware of the sponsorship arrangement and the sponsor's credits must be separated from all other editorial and advertising content on the channel.

Credits for the channel sponsor must not appear in or around programmes that cannot be sponsored and credits should not suggest that these programmes are included in the sponsorship arrangement.

The sponsor's presence on the channel should not be unduly prominent, and broadcasters will be unable to name channels after the sponsor.

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