Los Angeles  - The Screen Actors Guild, the largest union representing Hollywood actors, is to ask its members to authorize an open-ended strike after two days of mediation with film producers ended in deadlock, the union announced Monday.

The weekend talks between SAG and the Alliance of Motion Picture and Television Producers (AMPTP) were seen as a last-ditch attempt to bridge gaps between the sides over residual payments for work that is distributed through electronic media.

Producers wanted the actors to accept the same broad terms reached with smaller actors' unions and the writers' and directors' guilds.

However, despite 27 hours of talks over the weekend, federal mediator Juan Carlos Gonzalez was unable to bring the two sides together to hash out a new TV/theatrical contract, the Los Angeles Times reported.

"As previously authorized by the national board of directors, we will now launch a full-scale education campaign in support of a strike authorization referendum," SAG said.

"We will further inform our members about the core, critical issues unique to actors that remain in dispute." SAG needs 75 per cent of its 120,000 voting members to approve the measure in order to go forward with a strike.

The move was blasted by the AMPTP. "SAG is bizarrely asking its members to bail-out the failed negotiating strategy with a strike vote - at a time of historic economic crisis," the group said in a statement. "The tone deafness of SAG is stunning."

SAG members have been working without a contract since June 30, and prior to the weekend talks the sides had not met since talks broke down mid-July.

While the impasse increase the likelihood of a strike that could cripple film and TV production in the US, SAG's president Alan Rosenberg has said that a strike authorization vote does not necessarily mean the union will instantly go on strike.

Rather, the union believes the strike authorization would be a useful bargaining tool and give it more leverage in the talks.

Industry experts say that a strike referendum would take more than a month and that union leaders are expected to time any walkout to disrupt the Golden Globe Awards and Academy Awards early next year as studios plan their production schedules for 2010 movie releases. (dpa)