British cable operator Virgin Media has appointed Goldman Sachs to seek a possible buyer after it received approaches from various private equity firms, people familiar with the situation said on Sunday.

Carlyle Group, for one, offered in recent weeks to buy the company, whose leading shareholder is the flamboyant entrepreneur Richard Branson, the sources said, but they declined to disclose the price put forward.

Virgin's market capitalization is $8 billion, meaning any offer would likely exceed $10 billion based on the typical premiums paid in takeovers.

The company, whose shares are traded in New York but whose operations and customers are in Britain, also has another 6.1 billion pounds ($12.21 billion) of long-term debt.

Its shares closed at $24.37 on Friday on the Nasdaq.

The search for a Virgin Media buyer by Goldman Sachs was characterized by the sources as in the early stages.

Virgin and Carlyle both declined to comment. Goldman Sachs declined comment.

Virgin Media, which sells cable television, telephone, high-speed Internet and mobile phone services, was formed by last year's union of Britain's two cable operators NTL and Telewest. The new company then acquired Virgin Mobile from Branson and rebranded the entire group as Virgin Media.

It has about 15.3 million subscribers to its individual services, some of whom pay for more than one.

The company is locked in a pitched battle, including multiple legal fights, against satellite operator BSkyB (BSY.L: Quote, Profile, Research).

A group including Blackstone Group, Cinven, Kohlberg Kravis Roberts & Co. and Providence Equity Partners tried to buy Virgin Media last year, but was told its offer price was too low.

(Additional reporting by Kate Holton in London and Megan Davies in New York)