Fraternal filmmakers Peter and Bobby Farrelly said in April the original stars were reuniting in September for a follow-up.
But Carrey's representative confirmed an "Entertainment Tonight" report saying Carrey had grown "increasingly frustrated" by the lack of enthusiasm Warner Bros. and New Line are showing for the project.
Carrey wants to make the film but doesn't understand why making a sequel to the blockbuster appears to be a low priority for the studios involved, the report said.
"I would have thought 'Dumb and Dumber To' was a no-brainer," Carrey said in a statement to ET.com. "After all, it's implied in the title."
E! News said it is possible the studios aren't as excited about the film because the Farrelly brothers' last comedy, "The Three Stooges," underperformed at the box office.