Ross Brawn has called for the F1 calendar not to exceed a "sensible limit" of 20 grands prix.
With a provisional schedule for 2014 expected to be released in the next few weeks, the decision about the number of grands prix is heating up.
Most, however, feel 20 is enough.
According to Mercedes team boss Brawn, anything over that would be a strain on his team personnel and would become "difficult" to manage.
"Twenty races is pretty challenging for the teams with one crew of people," the Englishman told the Daily Express.
"I think you reach a need point that when you go beyond it you have to start looking at rotating people, rotating crews.
"That gets very difficult, particularly with the engineers because they are very closely linked with their drivers.
"That's not an easy thing, but with some of the technicians and mechanics and so on we can do that.
"But 20 races is pretty intense for everyone. One more is only five percent more; two is only ten percent more.
"But it really does start to get difficult to manage, so I think 20 is a sensible limit."