Angry Birds, in which players use a slingshot to attack pigs that try to steal the birds' eggs, has been downloaded more than 700 million times since its 2009 launch and turned small Finnish gaming firm Rovio into an enterprise valued at up to $9 billion.

Marketing chief Peter Vesterbacka told Reuters the company plans to roll out five new Angry Birds games this year, starting with Angry Birds Spaces in March, after introducing just one new game in 2011.

Angry Birds Spaces is set in outer space, with the firm using NASA's moon landing footage in a teaser video on YouTube.

"It is our first game launch in a year and our biggest game launch ever. We have very big expectations for it," he said.

Vesterbacka said the company was set to open first Angry Birds branded retail stores in China in a few months.

"We are just about to roll out our retail presence there, we are looking to get to a hundred stores very quickly. And I think there is a lot of potential to grow the numbers even further. We see huge potential in all of Asia," he said.

Vesterbacka said the firm was very happy with progress so far on Facebook, where it opened the game earlier this month.

"We are not the biggest game on Facebook but we are the fastest growing. We are making a lot of money already on Facebook," he said. "Of course, we want to have tens of millions of people on Facebook playing our game."

Rovio executives have said the firm would seek an initial public offering (IPO) in New York or Hong Kong, but the company was not in a rush to go public.

"We are profitable, we can fund our own growth," he said.

(Additional reporting by Elena Massa; Editing by Elaine Hardcastle)

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