'The Simpsons' may finish at the end of the next series.

The future of the long-running animated sitcom is reportedly in jeopardy because of a dispute of salary negotiations between the six main voice actors - Dan Castellaneta, Julie Kavner, Nancy Cartwright, Yeardley Smith, Hank Azaria and Harry Shearer - and studio 20th Century Fox Television, who have told the cast they must take a 45 per cent pay cut.

The cast - who currently earn around $8 million each for 22 weeks work - had offered to take a 30 per cent cut in exchange for a small percentage of profits taken from global syndication and show-related merchandise.

A source told The Daily Beast: "Fox is taking the position that unless they can cut the production costs really drastically, they'll pull the plug on new shows.

"The show has made billions in profits over the years and will continue to do so as far as the eye can see down the road. The actors are willing to take a pay cut of roughly a third, but that's not good enough for Fox."

A spokesperson for Fox Television admitted the show - which was created by Matt Groening and James L. Brooks - cannot continue "under its current financial model" but insisted they have not yet called a halt to negotiations.

The representative said: "23 seasons in, 'The Simpsons' is as creatively vibrant as ever and beloved by millions around the world. We believe this brilliant series can and should continue, but we cannot produce future seasons under its current financial model. We are hopeful that we can reach an agreement with the voice cast that allows 'The Simpsons' to go on entertaining audiences with original episodes for many years to come."

The show first aired in December 1989 and had a spin-off movie in 2007.