By Peter Bowes
BBC News, Los Angeles
Hollywood is in the midst of what has been called a 'virtual strike'.
Filming for the sequel to Transformers looks set to be delayed
With the biggest actors' union, the Screen Actors Guild (SAG), locked in protracted negotiations over a new contract, the entertainment industry is winding down in anticipation of another damaging stoppage.
SAG represents 120,000 actors in movies, TV and other media.
Scores of film and television projects have been put on hold because the studios do not want to risk having to halt production if actors walk off the job.
"It is a de facto strike," said Jack Kyser, chief economist with the Los Angeles County Economic Development Corporation, "It's sort of suspended animation."
"All the service providers - people that build sets, rent equipment, restaurants, the agencies, hotel, limo services - people aren't coming into town to shoot."
"It's a widespread impact and it's sort of de-stabilising an already somewhat unstable economy."
'State of flux'
Hollywood production is expected to stop altogether next week with only a few independent projects continuing because they have been given special permission by the union.
Tom Hanks is lending his support to the AFTRA contract deal
Major productions, such as the remake of Ridley Scott's Robin Hood and the sequel to Transformers, look certain to be delayed.
Hollywood is in a state of flux because no one knows how or when the actors' pay negotiations will end.
Their current contract expires on 30 June, although it is possible that negotiations could extend into July.
The Alliance of Motion Picture and Television Producers, which represents the studios, has said it is "committed to avoiding another harmful, unnecessary strike".
The Alliance points out that it managed to reach agreements with other Hollywood groups, such as the screenwriters and directors, earlier this year.
The issues at stake are similar to those that brought writers out on strike for 100 days last year.
The actors want a better deal when their work is sold on DVD and when film and TV clips are streamed on the internet.
The Screen Actors Guild (SAG) has the support of actor Jack Nicholson
"If we can't get a foothold in this new media, I swear to God, in 10 or 15 years actors like me will cease to exist, we'll become hobbyists," said the union's president, Allan Rosenberg.
Speaking at a recent rally by SAG members Rosenberg continued: "We'll have to get other jobs to support our acting habit and that is what is at stake here - the survival of the acting profession, the survival of the Screen Actors' Guild."
A feud between the acting unions is, in part, to blame for such a pessimistic outlook.
The American Federation of Television and Radio Artists (AFTRA), which represents 70,000 members, has already struck a deal with the studios and the union's membership is expected to vote in favour of the new contract in a ballot early next month.
For its part, SAG's leadership is actively campaigning to persuade the 44,000 actors who are members of both unions to reject the AFTRA deal.
"An interesting twist on this whole thing is the dispute between the screen actors and the AFTRA," said Mr Kyser.
Members of SAG rally outside the organisation's headquarters
"A lot of people are watching this and scratching their head because they feel that the Screen Actors Guild is being led by a bunch of hotheads, and they have really boxed themselves in."
Some of Hollywood biggest stars have also stepped into the fray.
Tom Hanks and Kevin Spacey have signed an online petition urging AFTRA members to accept the deal on offer from the studios, while Jack Nicholson and Ben Stiller have sided with SAG.
But there is no enthusiasm in Hollywood for another strike.
The entertainment industry is still trying to recover from the writers' stoppage and many people are still out of work.
"A lot of the shows haven't got back into production - they're looking now at starting production in July or August for the fall season, and if you do get a Screen Actors Guild strike that would just blow that all away," added Mr Kyser.