General Electric is understood to have agreed on a value of “about $30 billion” for the sale of a 51 per cent stake in NBC Universal to Comcast, America’s biggest cable operator.

The agreement brings one step closer a deal that has been under discussion for weeks. It would give Comcast a 51 per cent stake in NBC Universal, owner of television networks including NBC, USA Network and Bravo, along with local television stations, theme parks and a film studio.

GE initially would hold 49 per cent in the new venture. An option for GE to sell all or part of its stake in the new venture to Comcast within seven years has also been discussed.

An insider close to the talks said that the ongoing discussions were likely to involve some “give and take” on the final value of the deal.

Valuing Comcast’s cable networks, Vivendi’s 20 per cent stake in NBC Universal and the proposed new company itself had been a key issue in negotiations for some weeks. Comcast wanted to reduce the value of NBC Universal and increase the value of its cable networks to minimise the cash it would need to infuse in the new company.

Under the terms under discussion, the venture would consist of NBC Universal and Comcast’s collection of cable networks. Comcast would also contribute up to $6 billion (£3.6 billion). The parties have now decided that Comcast’s cash payment will depend partly on NBC Universal’s financial performance. If the unit’s performance worsens before the deal closes, Comcast could end up paying less, according to a person familiar with the negotiations.

The final deal could involve NBC Universal taking on debt to be used to buy out the GE and Vivendi stakes.

Spokesmen for GE and Comcast declined to comment.

GE, which owns 80 per cent of NBC Universal, has been considering its options in the event that Vivendi, its partner, chooses to sell its 20 per cent stake this year. The French company, which agreed to merge its Universal film studio, cable networks and theme parks with GE’s NBC businesses in 2003, has an annual option, from November 15 to December 10, to sell its minority stake. Vivendi has told GE that it wants to sell its stake this year, according to The Wall Street Journal, but it is understood not to have agreed to a deal yet.

Analysts hope that Vivendi, Europe’s largest entertainment group, will give some indication about its intentions on Thursday, when it announces its third-quarter results. It is expected to reveal a 0.1 per cent fall in underlying profit and a 2.3 per cent fall in revenue.

GE, America’s largest conglomerate, whose products range from jet engines to microwave ovens, has been under pressure for some time from many of its shareholders to offload NBC Universal, whose media and leisure businesses are considered misfits among its otherwise mostly industrial operations.

The company’s television stations have suffered a steep drop in advertising revenue and Universal Pictures has been struggling at the box office. The Universal Studios theme parks in Florida, California and Japan have suffered as a result of the depressed economy.

The sale would give GE a welcome cash injection. GE Capital, its financial business, has been dealing with rising losses on bad loans.

NBC Universal's Assets

NBC Entertainment: develops and schedules programmes such as The Jay Leno Show

NBC News: produces 25 hours of news programmes a week, including Today

NBC Television Network: broadcasts 5,000 hours of programming a year through about 200 affiliated stations

NBC Local Media Division: Comprises ten stations reaching 27 per cent of US TV households

Telemundo Network & Stations: Spanish-language network

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