Gabe Newell, managing director and co-founder of Valve, has confirmed plans for an Xbox 360 and PC demo of hotly anticipated zombie shoot-em-up Left 4 Dead.

Newell told at Leipzig Games Convention that it will include the first part of one of the four campaign 'movies', probably The Hospital level that has been demonstrated to the press.

He also confirmed that the demo will facilitate online cooperative play as well as single-player, although he couldn't confirm a release date for the demo.

Newell said: "We will be releasing demos for both the Xbox and for the PC. I don't know what the date is for release on that, though. I think it's going to contain the first part of one of the campaigns. I think it'll probably be Hospital but I'm not sure. That's a decision that Doug Lombardi is making."

When asked if you'll be able to play the demo online, Newell replied: "Oh yeah. You'll be able to play single-player and co-op in the demo."

Left 4 Dead is due out for PC and Xbox 360 on November 21 2008. Be sure to check out our hands-on preview right here.