Matt Groening and showrunner Al Jean told helmer Morgan Spurlock, who was interviewing the duo at the Mipcom sales mart for a creative keynote event, that making the series and producing the movie was so exhausting that a sequel remains a distant prospect.
"It took 18 years to get around to doing the movie," Groening said. "We got very frustrated. We thought it would take two years but it ended up taking four. Some day maybe we'll do another one -- but don't hold your breath."
As for when the tentpole toon might shut up shop for good, the pair indicated that the final bow was not on the horizon. The current U.S. season is the 21st.
"We cannot predict the end because we can't believe we are still here today," explained Groening.
Jean added, "We are contracted to do two more seasons following this one. I gave up predicting the end a long time ago."
Groening and Jean are in Cannes to celebrate the 20th anniversary of The Simpsons. The pair will be presented with the inaugural Mipcom Creative Icon Award at a gala dinner tonight.