An executive of Rovio, developer of the mobile game Angry Birds popular among users of Apple Inc's iPhone, said the company was worth several billion dollars, according to Finnish magazine Kauppalehti Optio.

Rovio Chief Marketing Officer Peter Vesterbacka told the magazine that a valuation of between $700 million and $1 billion, given in a Forbes report in July, was too low.

The company should instead be worth several billion dollars, he was quoted as saying, noting Facebook games company Zynga was estimated to be worth between $20 billion and $25 billion.

We are not selling though -- unless somebody offers enough, Vesterbacka was quoted saying in the interview published on Thursday.

Sky-high valuations of Internet-related and other technology stocks have come into focus particularly since the flotation of LinkedIn Corp, whose strong first-day premium helped spark talk of a repeat of the tech-stock bubble which burst in early 2000.

Rovio's chief executive told Reuters earlier this year that the company was aiming for a stock market listing in New York in two to three years.

The company has raised $42 million from venture capital firms Accel Partners, Atomico Ventures -- the firm started by Skype co-founder Niklas Zennstroem -- and Felicis Ventures.

(Reporting by Helsinki Newsroom; Editing by David Holmes)