A Russian company with a history of investing in online properties has expressed a strong interest in buying a chunk of Facebook, reports suggest.

Digital Sky Technologies is said to have offered $200 million (around £125 million) for a 2% stake in the social networking website, which means the site's overall worth is valued at $10 billion.

The Russian company is run by businessman and entrepreneur Yuri Milner, who is also said to have offered to buy up to a further $150 million of Facebook shares from investors - but is said to want a seat on the board as part of the deal.

In 2007 Facebook got funding from Microsoft when the software giant bought a 1.6% stake at a price that valued the site at $15 billion.