Vivendi shares rose on Tuesday as hopes mounted that Europe's largest entertainment group was close to selling its stake in U.S. media group NBCU and getting cash to fund its growth plans.

A source familiar with the matter said on Monday that Vivendi and General Electric Co , which owns 80 percent of NBC Universal (NBCU), had agreed in principle to a deal in which GE would buy Vivendi's 20 percent stake for $5.8 billion,

This would pave the way for Comcast Corp's proposed joint venture with GE and would give Vivendi extra funds for expansion, mainly in emerging countries.

Vivendi has been widely expected to part with the NBCU stake, a holding it has described as non-core as it is looking to simplify the group's structure around its telecoms, music, video games and pay-TV businesses.

Shares in Vivendi were up 2.9 percent at 19.74 euros at 0957 GMT (4:57 a.m. EST).

Several analysts, such as at UBS, said the price cited for the stake was slightly below expectations for $6 billion, and it remained unclear when the payment would be made.

UBS last month gained control of Brazilian telecoms operator GVT and has also recently bought some of the minority shareholders of its pay-TV unit Canal Plus.

From a liquidity standpoint, coming on top of the 1.2 billion euros bond raised a fortnight ago, if the group does receive $2 billion up front, this would leave it very comfortable buying in the remaining Canal Plus France minorities, which would be reasonably accretive, and then paying the dividend Q2 next year, Citi analysts said.

UBS called the sale of NBCU strategic, given the need to reduce leverage following the GVT deal.

The agreement is mainly the result of a meeting between GE Chief Executive Jeffrey Immelt and Vivendi's CEO Jean-Bernard Levy last week in Paris, where the two parties made progress on the talks that had been going on for weeks, the source said.

GE and Comcast declined to comment. A Vivendi spokesman declined to comment on Tuesday.

(Reporting by Dominique Vidalon, editing by Will Waterman)