Trey Parker and Matt Stone, creators of the animated hit comedy “South Park,” have accused the would-be buyers of their longtime partner Paramount Global of interfering with negotiations that could net them billions of dollars.

The two approached Paramount in February, telling the film and TV company that owns the show they want to keep making the series for many more years and extend a production deal that expires in 2027. The parties were already in talks to find a new streaming home for the series in a deal worth as much as $2.5 billion. HBO Max, which held the rights, was interested. So were several other companies, including Netflix Inc.

But Skydance Media, the independent film and TV producer that’s trying to buy Paramount, had ideas of its own. The company contacted HBO parent Warner Bros. Discovery Inc. and Netflix, relaying its own wishes on contract terms and deadlines. That triggered an angry rebuke from the creators of “South Park” and the threat of legal action, according to a letter reviewed by Bloomberg News.

“It has come to our attention that in recent days you contacted both Netflix and Warner Bros. Discovery to interfere in the process,” Parker and Stone’s lawyer said in the letter to RedBird Capital Partners, an adviser to Skydance and investor in the Paramount deal.

Paramount had planned to split the U.S. streaming rights to “South Park” between HBO Max and its own service, Paramount+. The HBO deal alone would have been worth more than $1 billion over 10 years, according to people with knowledge of the matter, while Paramount+ would have paid a similar fee for its deal.