UPDATE 2-Zucker to head new NBCU-Comcast venture -- sources

* Comcast, GE to make Zucker head of new joint venture

* Terms do not include a mandated exit for Zucker

* Comcast, GE still negotiating structure of new board

(Adds timeline, company comment, merger reasons)

By Jui Chakravorty

NEW YORK, Nov 10 (Reuters) - Comcast Corp (CMCSA.O) and General Electric Co (GE.N) have agreed to make NBC Universal CEO Jeff Zucker the head of their proposed joint venture, but the structure of a new board is still being negotiated, sources familiar with the matter said.

The two sides have been in talks to reach a deal that would give Comcast a 51 percent stake in the NBC Universal venture, which would also house the cable networks now belonging to Comcast. They recently agreed to value NBC Universal at about $30 billion, sources previously told Reuters.

Under the terms being discussed, Zucker will lead the new entity, with no clauses for him to leave after a specific period, the sources said on Tuesday. They spoke on condition of anonymity because the details have not been made public.

Comcast declined comment. NBC did not return calls seeking comment.