Television and movie writers are going on strike for the first time in 15 years in a dispute over fair pay in the streaming era.

The Writers Guild of America (WGA) said its 11,500 unionised screenwriters will head to the picket lines on Tuesday.

Negotiations between studios and the writers, which began in March, failed to reach a new contract before the writers’ current deal expired.

All script writing is to immediately cease, the guild informed its members.

The board of directors for the WGA, which includes both a West and an East branch, voted unanimously to call for a strike.

“The companies’ behaviour has created a gig economy inside a union workforce, and their immovable stance in this negotiation has betrayed a commitment to further devaluing the profession of writing,” the WGA said in a statement.

“From their refusal to guarantee any level of weekly employment in episodic television, to the creation of a ‘day rate’ in comedy variety, to their stonewalling on free work for screenwriters and on AI for all writers, they have closed the door on their labour force and opened the door to writing as an entirely freelance profession.

“No such deal could ever be contemplated by this membership.”

The Alliance of Motion Picture and Television Producers, the trade association that bargains on behalf of studios and production companies, said negotiations fell short of an agreement before the current contract expired.

In a statement, the AMPTP said it was prepared to improve its offer “but was unwilling to do so because of the magnitude of other proposals still on the table that the guild continues to insist upon”.

The dispute could hit TV and film productions depending on how long the strike lasts.