The first Promoted Tweet has appeared on the microblogging site Twitter, according to reports.
Greg Sterling of Search Engine Watch said the message, which appears in both global and local Trending Topics, is marked as "promoted".
It is an ad for the new Disney Pixar release Toy Story 3 and when users click the link, they are taken to a stream of tweets about the film.
Within these messages is a link to the company’s Facebook site, where visitors can buy tickets for US screenings.
Twitter first announced the introduction of Promoted Tweets in April, with co-founder Biz Stone saying they had been developed as an alternative to ads delivered by internet marketing services.
The messages come in the same 140-character format as normal tweets and they only appear as long as they are Retweeted or added to favourites to ensure they "resonate" with users.
Mr Stone said companies signed up for Promoted Tweets included Virgin America, Starbucks, Red Bull and Sony Pictures.
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