The opportunity is potentially too lucrative to miss, despite Ofcom's decision on tightening the rules for food and drink advertising to children, which will restrict commercials for foods high in fat, sugar or salt.
Coronation Street is the UK's most popular programme, regularly pulling in audiences of 10 million on four evenings a week.
The Cadbury deal, which has run for 10 years, is due to expire at the end of 2007 but will cease earlier if ITV finds a new sponsor. An ITV spokeswoman confirmed that companies from a "number of different categories" had already expressed interest.
With media channels and the grocery industry pushing for a grace period of up to a year to implement any new rules, the opportunity offers even producers of restricted products a high profile shop window in the short term.
CTB denied that its move was linked to the long-awaited Ofcom announcement, explaining that it wanted to focus on advertising individual brands to specific audiences. "It has absolutely nothing to do with any change in the advertising rules," said head of customer relations Mike Tipping. "We have been working on a new strategy for months."
The deal, which dated back to 1996, had initially been for two years only.
"Both parties have had tremendous value out of this relationship but we're moving away from an overall strategy, with different brands targeting different consumers," said Tipping.
CTB is set to embark on a 2007 NPD programme that includes a relaunch for its dark chocolate brand Bournville and a premium Double Chocolate version of its flagship Dairy Milk, both of which are likely to target an older, more sophisticated consumer than the average Coronation Street viewer.
A new £3m strand of advertising to back the relaunch of its Snaps brand breaks next week. It features a woman reluctantly sharing Snaps with friends over coffee.