Thousands of writers brandishing placards and clad in red t-shirts gathered outside Fox Studios in Century City to protest, in the biggest single demonstration since the strike began on Monday.

The writers' stance has earned sympathy from many Hollywood celebrities, including Louis-Dreyfus, Longoria and Kelsey Grammer of Frasier, who also attended the rally.

"Now people are, you know, drawing their lines and I'm hoping that the lines can be blurred enough that people come back together and start talking," Grammer told local television station ABC7.

"It affects the economy of Los Angeles."

The Writers Guild of America (WGA) pressed ahead with a strike after last-ditch talks with Hollywood producers over the issue of payment from Internet sales and downloads broke down on Sunday.

The industrial action is the first by the WGA for nearly 20 years and has plunged the industry into turmoil, halting production on hit television shows like Desperate Housewives and forcing the postponement of 24.

Popular late night chat shows hosted by Jay Leno and David Letterman have also shut down this week because of the strike, which industry analysts believe may last several months. © 2007 Australian Broadcasting Corporation