Konami is the first publicly traded games company to join the service, which was announced last week, in a sign that Zynga is gaining momentum finding publishing partners willing to share revenue with it. The service has now signed on six publishers.

The website, Zynga.com, became open to the public on Monday, allowing users to make personal profiles and play games.

The service is the online game company's most aggressive move yet to create a presence outside of Facebook, where it makes 93 percent of its revenue. Zynga went public in a much anticipated initial public offering last December.

Rob Dyer, head of partner publishing at Zynga, told the Game Developers Conference in San Francisco on Thursday that Konami is working on a new game that will be published on Zynga.com at a future date.

"We're dedicated to creating the best destination for social games for players and developers alike," Dyer said.

Zynga is offering companies technology, analytics and the chance to market games to Zynga's 240 million monthly users.

Playdemic, another games company, will bring social games "Gourmet Ranch" and "Crossword Buddies" to the platform, while publisher Rebellion will make a new social game for Zynga, the companies said in a statement.

Zynga's redesigned website will make it easier for users to begin playing games quickly, by offering features not available on Facebook such as access to live chatting and a message board where they can ask for help.

But the so-called Zynga Platform still retains close ties to Facebook, as users must log in with their Facebook IDs and players will use Facebook Credits, the social network's payment system, to trade in the games' virtual houses, tractors, costumes and other goods.

(Reporting by Liana B. Baker; Editing by Edmund Klamann)

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