In a new online advertising twist, one US-based VoIP provider has created a method of sending ads to the user depending on what they are talking about.

Pudding Media is trying to take advantage of the advertising potential of its user base by allowing marketers to display adverts of users' screens if the conversation mentioned topics highlighted in new terms.

"For example, a consumer talking about movies may see links to trailers, reviews and show times," the company explains.

Chief executive and co-founder of the firm, Ariel Maislos, said that the voice-activated adverts should let "brands reach consumers with more targeted, relevant offers and communications providers gain a new revenue stream".

The company said that tens of thousands of keywords are set to be made available for marketers to pay for, while there will also be the ability for advertisers to highlight special offers using the service.

Pudding Media also suggested that other VoIP operators may use its technology to run ad-supported voice-calling plans of their own in the future.