Facebook is not working on opening up the world's biggest social network to children under the age of 13 in the short term, founder and Chief Executive Mark Zuckerberg said Wednesday, contradicting some media reports.

Facebook, which has more than half a billion active users, operates policies around the world not to register children under a certain age. The age varies by country but is typically around 13.

We're not trying to work on the ability for people under the age of 13 to sign up, Zuckerberg said when asked about the issue at the e-G8 Internet forum in Paris Wednesday.

Zuckerberg said comments he had made at a conference last week at an education conference, when he said regulations made it difficult for children to sign up for Facebook, had been taken out of context.

He said the complexity of protecting children online meant the question was not a priority for the company.

That's just not top of the list of things for us to figure out right now, said Zuckerberg. Some time in the future, I think it makes sense to explore that, but we're not working on it right now.

Zuckerberg began the on-stage interview by batting away a question about Facebook's plans to go public with the answer: Not yet. The company is expected to offer its shares to the public next year.

Facebook is expected to generate roughly $4 billion in advertising revenue in 2011, up from $1.86 billion a year earlier, according to market research firm eMarketer.

Its value has been estimated at up to $90 billion, based on private transactions on the secondary market.

Zuckerberg also played down the role his social network had played in revolutions that have rocked countries from Tunisia to Egypt to Libya.

It's not a Facebook thing, it's an Internet thing, he said when asked about Facebook's part in the so-called Arab Spring. I think Facebook was neither necessary nor sufficient for any of those things to happen.

If it weren't Facebook, it would be something else.

Millions of users in the Middle East have used Facebook and Twitter to organize protests in recent months.

(Reporting by Georgina Prodhan; Editing by Will Waterman)

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