Television viewers face watching "personalised advertisements" under a new plan that will target people depending on their consumer habits, it has emerged.

Broadcasters are set to introduce advertisements based on personal tastes to halt the growing shift from television to the internet.

The "personalised" advertisements would use information gathered from viewer preferences, where they live and other "customer research". Experts said the plans would likely end of the traditional "one size fits all" advert break.

BSkyB is trialing a plan called AdSmart, which will store advertisements on their customers' Sky+HD set-top boxes.

Under the plan, which will start being rolled out within two years, adverts would be transmitted during "live" viewing. The timing and length of breaks will remain unchanged.

Figures show that an estimated 50 per cent of all advertising spend is wasted. Advertising agencies are said to be broadly supportive of the move as it could stop traditional "channel-hopping".

They hope it will help eradicate wastage in TV advertising by helping remove ads which are irrelevant to certain homes.

A BSkyB spokesman said it hoped to "help advertisers offer more relevant adverts".

"This might include using postcode information to offer more localised ads or providing ads which are more likely to be of interest to them based on their interests or circumstances," he said.

"It will also mean updating ads so that even when watching recorded programmes they are still up-to-date."

BSkyB officials stressed that they would not target customers by "analysing which programmes individual viewers watch" and it would not purchase data about purchasing habits.

Tim Lefroy, the chief Executive of the Advertising Association, said it was another "great step for consumers".

"It offers products, services, offers and information about the brands they trust where and when it is most relevant to them," he said.