The two sides hope to get a deal done in two to three weeks, CNBC reported on Friday, citing sources familiar with the talks. But the person close to the talks told Reuters an agreement was unlikely within that timeframe.
NBC Universal would become a joint venture that is 51 percent owned by Comcast and 49 percent by GE.
Comcast is expected to contribute $4 billion to $6 billion in cash plus its cable network assets, which include E! and The Golf Channel, for control of a new separate NBC Universal whose assets include Bravo, USA and CNBC among others as well as a movie studio and theme parks.
GE, which is has been pressured by investors to offload its 80 percent stake in NBC Universal, is considering a host of proposals for NBC Universal as partner Vivendi SA explores whether to sell its 20 percent stake.
Currently, the plan is for GE to buy Vivendi's stake, and put the debt funding the deal on NBC Universal's balance sheet.
Shares of Comcast fell 2.7 percent on Friday, bringing the drop since news of the deal leaked on Thursday to nearly 10 percent.
(Reporting by Yinka Adegoke; Editing by Richard Chang)