Hollywood writers overwhelmingly voted to approve a hard-fought new deal with studios, their union said Monday, officially ending one of the industry's longest ever strikes.

"99 percent of WGA members have voted in favor of ratifying" the contract, allowing them to return to work on improved terms, said the Writers Guild of America on social media.

Approval by the union's 11,500-odd members had been widely seen as a near-certainty.

Last month, after 148 days on strike, WGA negotiators reached a deal with the likes of Netflix and Disney, achieving better pay, greater protections from artificial intelligence, minimum staffing levels and more.

Most writers returned to work nearly two weeks ago, in anticipation of the deal being ratified.

Still, film and television productions in Hollywood are yet to resume in earnest, as the far larger Screen Actors Guild (SAG-AFTRA) representing 160,000 performers remains on strike.

Talks between the studios and SAG-AFTRA, which went on strike in July, finally began last week, and were scheduled to resume Monday.

SAG-AFTRA's demands over pay, and limits to the future use of AI, go further than those of the writers.

The Alliance of Motion Picture and Television Producers, which represented the industry's biggest studios in talks with the WGA, praised the outcome of the writers' vote.

"The AMPTP member companies congratulate the WGA on the ratification of its new contract, which represents meaningful gains and protections for writers," it said in a statement.

"It is important progress for our industry that writers are back to work."