Ferrari have cast doubt on the prospects of a Rome Grand Prix by saying Italy, whose Monza circuit is one of Formula One's great venues, can only ever host one race a year.
"Our position is very clear and leaves no room for interpretation," team boss Stefano Domenicali told the ferrari.com website.
"Our sport is increasingly expanding the number of countries hosting a grand prix and all the teams are in agreement about that.
"Therefore it is inevitable that it will no longer be possible to have two races in the same nation. It's not the job of the teams who choose where a grand prix is held, that's up to the commercial rights holder."
Spain is currently the only nation with two races, one in Barcelona and the other - the European Grand Prix - in Valencia.
The calender is expanding to a record 20 races in 2011 with India making its debut after South Korea held its first race this year.
A US GP in Austin is scheduled for 2012 with Russia arriving in 2014 with a race in Winter Olympic venue Sochi.
Rome wants a race through the streets of the EUR district from 2012 or 2013 and has signed a letter of intent with commercial supremo Bernie Ecclestone.
However there is opposition from some local residents.