WASHINGTON DC, United States—Hot social networking site Facebook said Tuesday it has introduced a dual-class stock structure but has no plans to go public for the moment.

"Facebook is a private company so we don't typically share details on stock-related matters," the Palo Alto, California-based company said in a statement.

But the firm said it introduced a dual-class stock structure "because existing shareholders wanted to maintain control over voting on certain issues to help ensure the company can continue to focus on the long-term to build a great business."

Facebook said creating the new stock structure did not mean it was preparing an initial public offering.

"This revision to the stock structure should not be construed as a signal the company is planning to go public," the statement said. "Facebook has no plans to go public at this time."

The Wall Street Journal said Facebook was converting the shares of all current shareholders into Class B stock, which carries 10 times the voting power of Class A stock.

The newspaper noted that Facebook chief executive and co-founder Mark Zuckerberg, the company's largest shareholder, has said that it plans to go public eventually.

A Russian Internet company offered in July to purchase $100 million worth of stock from Facebook employees in a deal that valued the company at $6.5 billion.

US software giant Microsoft bought a 1.6 percent stake in Facebook in 2007 for $240 million, valuing the social network on paper at $15 billion.

Facebook announced in September that it had signed up its 300 millionth member.