LOS ANGELES – Hollywood writers and studio representatives began last-ditch negotiations Sunday in an effort to prevent a strike, the writers union said.

A federal mediator called the meeting between the Writers Guild of America and the Alliance of Motion Picture and Television producers at an undisclosed location.

The writers’ contract expired Oct. 31, and they plan to strike at 12:01 a.m. Monday if a deal cannot be reached. The first picket lines would be seen at New York’s Rockefeller Center, followed by picket lines at various locations in Los Angeles, the guild said.

The writers want more money from the sale of DVDs and a share of revenue generated by the sale of TV shows and films over the Internet. The studios say the demands are unreasonable and would hamper attempts to experiment with new media.

The last time writers went on strike was in 1988. The walkout lasted 22 weeks and cost the industry about $500 million.

WGA board members voted unanimously Friday to begin the strike unless studios offered a more lucrative deal. The two sides have been meeting since July.

“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.