Talks on the sale of Vivendi SA's NBC Universal (NBCU) stake to General Electric Co hinge on when Vivendi would get paid as well as how much, people familiar with the matter said on Friday.

The two sides are up to $1 billion apart in valuing Vivendi's 20-percent stake in NBCU, the sources said.

Vivendi values its stake at $6.1 billion, one of the sources said. It also wants to get paid for its stake upfront rather than wait for the closure of a deal between GE and Comcast Corp over NBCU, the sources said.

GE's proposed deal with Comcast involves turning NBCU into a joint venture, 51 percent owned by Comcast and 49 percent owned by GE. Comcast would contribute between $4 billion and $6 billion in cash, as well as its cable assets, to pay for its stake.

Vivendi did not return calls asking for comment.

Vivendi has an annual month-long window that runs until December 10 in which to exercise an option to sell the stake back to GE.

It could also demand an initial public offering for NBCU instead, putting it in a strong bargaining position if GE and Comcast are in a hurry to get the deal done.

There is a conflict between the normal exit provision, through the yearly window, and the deal allegedly being negotiated between Comcast and GE, Vivendi's finance chief told Reuters this week on the sidelines of an investor conference.

If we do send them a letter today saying we'll trigger, meaning we want an IPO in the spring, it's not consistent with the fact that they are signing a deal with Comcast that does not include an IPO, Philippe Capron said at the event in Barcelona.

POSTURING

As well as media assets that include the world's biggest recorded-music company, Universal Music Group, Vivendi owns telecoms assets which it has ambitious plans to expand in emerging economies.

Last week, it beat rival Telefonica to gain control of Brazilian telecoms group GVT in a deal valuing GVT at $4.8 billion.

But Vivendi has made it clear it will tap available credit lines of 6 billion euros ($8.9 billion) for the acquisition, and does not need to sell the NBCU stake.

Citi analysts wrote in a note on Friday: There seems a good deal of posturing on all sides, and said they valued Vivendi's stake at $5.9 billion.

The real question, aside from the contractual rights Vivendi has, is how valuable their 20 percent stake is to the structure of the deal between Comcast and GE, they wrote.

Vivendi's liquidity rights (right to force an IPO at some point) may well be unappealing to Comcast as a potential majority owner of NBCU over time. As such, we think that Vivendi's leverage in negotiations will be reasonably strong.

Vivendi shares were down 0.5 percent at 19.07 euros by 1600 GMT, in line with the DJ STOXX European Media index <.SXMP>.

Selling its NBCU stake would give Vivendi more financial headroom, notably if it were to seize further acquisition opportunities in emerging countries, CFO Capron said.

Proceeds could be also used to help the group stick to a policy of protecting its investment-grade rating and strong dividend if it were to seal more deals in emerging countries or buy out minorities in its Canal Plus broadcasting unit.

Most analysts believe a compromise over valuation is likely, though they feel selling the 20 percent stake is not vital for Vivendi's financial health.

Following the GVT deal, we believe Vivendi will ultimately sell its stake in NBCU, but not at any price... Similarly, GE needs Vivendi's stake for Comcast for the tie up to go through and we see a compromise as likely, UBS wrote in a note.

(additional reporting by Quentin Webb, Georgina Prodhan and Anupreeta Das)

(Editing by Sitaraman Shankar)

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