CNN  — 

The striking writers and heads of the four big Hollywood studios have concluded a “marathon session” of negotiations, which lasted more than ten hours, without a deal, a person familiar with the matter told CNN.

The person, who requested anonymity because they were not publicly authorized to discuss the matter, said that more progress was made during the negotiations Thursday, the second straight day of talks between the two sides, but a deal still has not been inked to end the historic Hollywood work stoppage.

It’s unclear when the studios and writers will meet again to continue negotiations.

The Alliance of Motion Picture and Television Producers studio bosses — Warner Bros. Discovery chief David Zaslav, Disney chief Bob Iger, Netflix co-chief Ted Sarandos, and NBCUniversal studio chairman Donna Langley — resumed negotiations on Wednesday with the Writers Guild of America. After the meeting, both sides issued a rare joint statement.

“The WGA and AMPTP met for bargaining today and will meet again tomorrow,” they said on Wednesday.

The fact that the two sides — which at times have rebuked each other for comments to the media — issued a joint statement signaled a possible sign of progress.

Warner Bros. Discovery is CNN’s parent company.

The WGA went on strike May 2 with the work stoppage reaching its 143rd day on Thursday, putting it within two weeks of the longest strike in the union’s history, which lasted 154 days in 1988. Many productions had halted even before SAG-AFTRA joined the WGA on strike July 14.

Both sides have similar sets of demands, including better wages, residuals payments from streaming services for their work, and job protections against the use of artificial intelligence.

- CNN’s Chris Isidore contributed to this report