UK commercial radio stations are setting aside their rivalries to form an alliance against their perceived common foe - state-owned broadcaster, the BBC.

Executives from a number of Britain's leading commercial radio groups, including the newly formed GCap, Emap, Chrysalis and Virgin Radio, have been in informal talks about bringing in more nationally known broadcasters and shows.

The move comes amid warnings about volatile national advertising revenues and radio's battle to retain its share of national marketing budgets.

UK local radio stations are obliged to carry a significant amount of local content. Operators want to avoid undermining their appeal to local advertisers, particularly as local advertising is proving more resilient than national.

Howard Bareham, head of radio at media buying group MindShare, says "localness is the strength of the medium" but adds that, faced with the BBC's cross-promotional powers, "commercial groups realise they have to work together".

The syndication strategy could encompass musical genre shows, entertainment news and new national formats.

According to latest figure from RAJAR (Radio Joint Audience Research), the BBC has a 10% lead over commercial radio in total audience share. However commercial stations have the majority share of the 15-44 demographic, prized by advertisers.

The broadcasters will co-operate for next month's Live8 anti-poverty concerts, echoing a similar initiative in January for the Asian tsunami victims, which lifted commercial listening among people aged 15 or over by 7%.

Data sourced from Financial Times online; additional content by WARC staff