The Facebook social networking site could be worth as much as $6bn (£2.95bn), according to Bear Stearns analyst Robert Peck.

Peck made his claims in a note to clients, based on the company's current revenue and predicted future earnings.

The analyst expects Facebook to generate $140m in revenue in 2007, with that figure jumping to $358m in 2008.

By 2016 Peck predicts an explosion in revenue up to $6bn, generating $2.3bn in pre-tax earnings.

Those calculations form the basis of his advice that Facebook is worth "as much as $5-$6bn".

Despite already having a $1bn bid turned down, Peck expects Yahoo to make an improved offer if it doesn't want to "risk becoming a marginal player in this rapidly growing space".

And he believes a significantly-improved offer would secure the site for Yahoo.

"When it comes down to it, we think the price tag is the ultimate factor for a transaction to materialise," he said.