But Russia is joining the action next season, and F1 business journalist Christian Sylt wrote in a City A.M. report that talks are on with Mexico and Thailand.
"Having races in the right place is what matters," F1 chief executive Ecclestone told Sylt.
"The teams could probably deal with 22 races."
The 82-year-old also said he would like Africa to host a race in the future.
"I want to be in Cape Town," said Ecclestone. "I have been offered Durban but I think we would be better off in Cape Town."