Some of the world's biggest media companies are lining up to take on YouTube at its own game - and launch a rival online video service.

News Corporation , owner of the Fox TV network , 20th Century Fox movie studio and MySpace , are apparently teaming up with media giants NBC Universal and Time Warner AOL to deliver legal TV shows and movies on the as yet unnamed service. It has also roped in Microsoft and Yahoo! , according to a report in the Los Angeles Times . The official announcement is expected later today.

At least some in this new online video camp are steering away from reports that the new service could be a "YouTube killer." At a conference in March Peter Levison, head of News Corps' Fox Interactive Media said: "We're certainly not describing it as such. If they do, MySpace will be a huge beneficiary of that.

Also expected to sign up for the service - which is expected to launch in the US only this summer - is Viacom . The media company has recently been in the news for trying to sue YouTube for $1 billion over breach of copyright on videos posted to the YouTube site.