Amazon is said to be in talks with a number of FMCG firms, including P&G and Clorox, regarding potential advertising on its Echo device, according to a report published by CNBC.

CNBC sources reveal that promotional opportunities would operate in a similar way to paid searches on Google, with companies paying for higher placement if a user searches for a given product. Other opportunities include targeted advertising, allowing its voice-powered Alexa device to suggest products based on purchasing history or to recommend particular brands when asked for advice on a given subject.

A spokesperson for Amazon told CNBC that the company had no plans to add advertisements to Alexa, while Clorox declined to comment when contacted by CNBC. The number of people in the US using voice-enabled search devices doubled in 2017 to 36 million, with Amazon accounting for 71 percent of the market.