US media giant Viacom and the nation's biggest cable television operator, Comcast, are said to be in talks on a joint venture.

The preliminary discussions, reported in the New York Post, are believed to focus on creating new cable TV channels aimed at viewers aged between 25 and 54.

Neither side has commented, but Viacom's co-president Tom Freston says the company's MTV Network unit has contacted a number of unspecified cable operators.

MTV is looking to expand its audience from traditional children's, teen's and young adult programming into lifestyle shows for an older demographic.

A partnership with Comcast, which has 21 million subscribers in the US, would guarantee MTV that its new channels would get off the ground and could help future negotiations about carriage of its cable channels on Comcast systems.

Comcast would add another dimension to the programming business it has been expanding since last year.

Data sourced from Wall Street Journal Online; additional content by WARC staff