Formula One's governing body would like the season cut back to 16 grands prix in future, its president Max Mosley said on Monday.
Some of the European races could face being dropped
This year there are 18 races on the F1 calendar but FIA chief Mosley said some European races could be axed.
"In the long term it will be difficult to maintain the smaller races and it is also going to be difficult to have two races in one country," he said.
Germany and Italy currently both have two grands prix.
F1 supremo Bernie Ecclestone said at the weekend that this season would see the last race at the Italian track of Imola.
He also told Italian newspaper Gazzetta dello Sport that the sport could cope with 20 races if there was no testing.
But Mosley said the FIA would not favour such a scenario.
"In the longer
term we would prefer to see 16 races," he said.
"I think what we
will end up with is hardly any testing but not 20 races. It is questionable whether you need 20 grands prix."
There were meant to be 17 races this season but the French Grand Prix was given a reprieve after being initially axed because of funding problems.
Mosley re-iterated on Monday that the race at Magny-Cours will definitely go ahead in July.
"It is now back on the
calendar without question so far as we are concerned," he said.