Viacom lost out on a bid for MySpace last year to News Corp, which acquired the portal for $580m, but Bebo represents a second chance for the US-based media giant to match MySpace's phenomenal success.
The news follows yesterday's announcement that Viacom finalised a deal with Google to make content available through the search engine giant's network of blogs and websites.
Bebo has far fewer users than MySpace, with the company claiming it has 25m registered users worldwide in comparison with MySpace's 100m, but according to Nielsen/NetRatings, it is the UK's second most popular social networking portal behind MySpace, which has 2.7m users.
According to media reports, BT recently made a bid of around $571m for Bebo, but was told to "think north of $1bn".
Michael and Xochi Birch, the co-founders of the San Francisco-based Bebo, are understood to have been visiting UK media companies in the last week, prompting speculation that details of a possible deal could become available soon.
Viacom has been in the market for user-generated content social networking products for some time, and is keen to add to MTV Flux, an offshoot of the music channel which allows viewers to upload their own content.
Despite it having only a quarter of the registered users of MySpace, Bebo is viewed as a highly lucrative revenue generating investment because of its strong links with youth marketing and potential for online ad sales.
In May Bebo received an £8m investment from Benchmark Capital, the owners of Irish pay-TV group Setanta, and it is understood the revenue will be used to drive Bebo's blogging, home video and user-generated content technology, with a sum being put aside to open up a London office.
Birch claims he receives a bid for Bebo "about once a fortnight", despite only setting up the company just under a year ago.
He declined to comment on whether Viacom had made an offer for Bebo, but confirmed that most interest for the portal came from traditional media companies.
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