Producer Arthur Sarkissian told Crave that he is hoping to bring in a pair of new characters to reinvigorate the franchise.
"I am working on Rush Hour 4 right now with Chris Tucker and Jackie Chan," he said. "I'm trying to do it closer to how I did Rush Hour 1, more down to earth, more gritty, introduce two new characters and make it real the way the first one was.
"I personally was not happy with the third one. I thought 1 and 2 were very good. I think 3 got out of hand a little bit. It's not a matter of just bringing them back to do another segment of that or a sequel to it by putting them in another city and having them bicker. I don't want that. I want something new."
Sarkissian suggested that he is hoping to lure Oscar-winning The Help star Octavia Spencer to join the sequel's main cast.
Sarkissian added that no screenwriter has been enlisted to pen the script and Rush Hour franchise director Brett Ratner is "more than welcome to do it but he's got to do it in the right way".
On whether Chan would be undertaking strenuous action scenes, Sarkissian said: "He's getting a little older. I think he can fit it. What was great about Rush Hour 1 and 2 mostly was the relationship of these two and it came out of nowhere.
"It was just very real. We didn't build it, we didn't write it. It just happened. I think the action will be there but it has to be moulded to fit him today and not forced into stuff that he won't do."
Chan said during May's Cannes Film Festival that he couldn't foresee ever returning to the action comedy series.
The previous three Rush Hour movies have grossed more than $800 million at the worldwide box office. The most recent instalment, Rush Hour 3, was released in 2007.
Watch the trailer for Rush Hour below: