Members of the Writers Guild of America (WGA)are now on strike after the failure of last-minute negotiations.
The union met for 10 hours with the Alliance of Motion Picture and Television Producers (AMPTP)on Sunday but there were still major sticking points, particularly onpayments forDVD releases.
The current contract between the WGA's 12,000 writers and producers expired on Wednesday.
Members of theEast Coast division of the union were told they would be on strike from midnight (7am GMT) with picketing expected to starton Monday morning.
An AMPTP spokesman called the action 'irresponsible.'
The immediate impact will be felt on US chat shows and television soaps but the effects are likely to be felt far more widely - particularly as they set a precedent whenactors and directorsrenegotiate their contracts next June.
The last writers' strike took place in 1988.