Comcast Corp. appears days from completing a $30 billion joint-venture deal for NBC Universal Inc. A deal could be announced later this week or, more likely, early next week, according to sources.

Vivendi, the French media conglomerate, still is a factor in the negotiations and has not said whether it would sell its 20 percent stake in NBC Universal to General Electric. Vivendi owns 20 percent of NBC Universal, and General Electric owns the other 80 percent.

The joint-venture talks have taken place primarily between GE and Comcast, and sources say the complex deal could unravel because of Vivendi, although that seems unlikely.

Vivendi has said it viewed ownership of NBC Universal as "not core" to its business. None of the companies would comment for the record.

The Wall Street Journal reported yesterday that Comcast and GE had agreed to value NBC Universal at $30 billion.

GE is seeking $30 billion for the purchase, while Comcast is seeking to come under $30 billion, sources close to the negotiations say.

In the deal, Comcast would acquire 51 percent of NBC Universal at first, then boost its ownership to 100 percent over seven years.

The Philadelphia cable company would combine its entertainment programming assets - E!, Style, Versus, the Golf Channel, and regional sports networks - with those of NBC Universal. Comcast also would pay $4 billion to $6 billion in cash.

NBC Universal's entertainment assets include the cable-TV networks USA, Bravo, and Syfy; Universal Studios in Hollywood; and the ratings-challenged NBC broadcast network in New York.

GE and Comcast are eager for different reasons. GE would like to unload the entertainment programmer for billions in cash and to focus on industrial businesses. Comcast would like to own a leading entertainment company to boost growth prospects.

NBC Sports is attractive to Comcast, which could combine NBC sports operations with Comcast's Versus sports channel to challenge ESPN, some believe.

Analysts say Comcast is purchasing NBC Universal at a favorable time, with the value of entertainment companies depressed because of the soft advertising market and a swift decline in DVD movie sales this year.

But the deal holds dangers. NBC Universal will be loaded with debt, and the economy remains very weak.

Comcast stock has taken a beating since Sept. 29, or about the time that news leaked of the Comcast-GE talks. The stock closed yesterday at $15.15, compared with $17.38 on Sept. 29. That's a 12.8 percent decline.

Over that time, Time Warner Cable stock slipped just 4 percent - to $42.10 yesterday from $43.75 on Sept. 29.

The Dow Jones industrial average has advanced 5 percent, or 483 points, to close yesterday at 10,226 in the same period.

The Federal Trade Commission and Federal Communications Commission are expected to closely examine a merger of Comcast and NBC Universal for anticompetitive concerns. Brian Roberts, Comcast's chief executive officer, said in a conference call last week that Comcast had not seen any "red flags" from the Obama administration that would make the cable company believe it couldn't obtain approvals.

Comcast is one of the nation's largest purchasers of entertainment programming. But the company's core competency has been running cable operations and advancing Internet penetration in cable franchise areas - not developing hit TV shows.

It's unclear how Comcast would run NBC Universal or who would run it. Jeffrey Zucker heads NBC Universal in New York. But he hasn't reversed terrible prime-time ratings at the NBC broadcast network.

Stephen Burke, the No. 2 management executive at Comcast, behind Roberts, is considered talented in entertainment. The top entertainment executive at Comcast is Jeff Shell, who formerly was president of News Corp.'s Fox Cable Networks Group. He joined Comcast in 2005. Peter A. Chernin, a former president of News Corp., is advising Comcast on NBC Universal.

Contact staff writer Bob Fernandez at 215-854-5897 or bob.fernandez@phillynews.com.