Writers Guild of America board members voted unanimously Friday to begin the strike at 12:01 a.m. Pacific time (3:01 a.m. EST) unless studios offered a more lucrative deal with a bigger cut from video sales and shows sold or streamed over the Web.
"The studios made it clear that they would rather shut down this town than reach a fair and reasonable deal," Patric Verrone, president of the western chapter of the guild, said at a news conference.
The union said it would stage its first pickets in New York and Los Angeles after strike captains meet Saturday to finalize details.
Both sides agreed late Friday to meet with a federal mediator on Sunday in a last-ditch effort to avoid a strike. The meeting will take place at a neutral location to be determined, the Alliance of Motion Picture and Television Producers said.
Earlier in the day, J. Nicholas Counter, president of the producers' group, called the writers' strike "precipitous and irresponsible" in a prepared statement.
Producers believe progress can be made on other issues but "it makes absolutely no sense to increase the burden of this additional compensation" involving DVDs and the Internet, he said.
Last year alone, members of the western chapter of the guild were paid $56 million in additional compensation from DVD residuals, he said.
Counter declined a request by The Associated Press for further comment.
Among other media giants, the alliance represents CBS Corp.; NBC Universal, a unit of General Electric Co.; and The Walt Disney Co., owner of the ABC network.
The negotiations began in July and were joined this week by a federal mediator.
"We are committed to seeing this through and are willing to engage in any further discussions if the studios so desire," Verrone said.
The first casualty of the strike would be late-night talk shows, which are dependent on current events to fuel monologues and other entertainment.
"The Tonight Show" on NBC will go into reruns starting Monday if last-ditch negotiations fail and a strike begins, according to a network official who spoke on condition of anonymity because the person lacked authorization to comment publicly.
Garth Brooks and Tommy Lee Jones were the scheduled guests.
Comedy Central has said "The Daily Show with Jon Stewart" and "The Colbert Report" would likely go into repeats as well.
A message left seeking CBS comment on plans for "The Late Show with David Letterman" in New York was not immediately returned Friday evening.
During the 1988 writers strike, Letterman, then host of NBC's "Late Night," and longtime "Tonight Show" host Johnny Carson initially went off the air but later returned as the walkout dragged on for 22 weeks and cost the industry about $500 million.
Daytime TV, including live talk shows such as "The View" and soap operas, which typically tape about a week's worth of shows in advance, would be next to feel the impact.
The strike will not immediately impact production of movies or prime-time TV programs. Most studios have stockpiled dozens of movie scripts, and TV shows have enough scripts or completed shows in hand to last until early next year.
There could be widespread disruptions in Hollywood as other unions support the writers.
Officials with the Screen Actors Guild have told members they must report for work but encouraged them to join picket lines during their off-time.
A similar message came from the head of a local Teamsters union. However, those workers were told they were protected by law from employer retribution if they honored strike lines.
John Bowman, chief negotiator for the writers guild and the producer on an upcoming TBS show "Frank, TV," said he would not cross picket lines, even if it cost his job.
"Unfortunately we have to inflict as much damage as we can as soon as possible in order to get this thing over," he said.
The economic impact of a strike is hard to estimate because not all production will be halted at once, economists said.
"There definitely will be pain," said Jack Kyser, chief economist for the Los Angeles Economic Development Corp.
The entertainment industry contributes about $30 billion a year to the Los Angeles economy, or about $80 million a day, he said.
Talks between writers and producers will likely impact upcoming negotiations between the studios and unions representing actors and directors.
All those unions believe revenue from content offered on the Internet, cell phones and other platforms will grow tremendously in the years ahead, even though it's now minuscule compared to DVD sales.
Consumers are expected to spend $16.4 billion on DVDs this year, according to Adams Media Research.
By contrast, studios could generate about $158 million from selling movies online and about $194 million from selling TV shows over the Web.
The strike was first announced Thursday night at a meeting attended by 3,000 union members whose moods ranged from defiant to somber.