Formula One's governing body sought urgent clarification from French motorsport authorities on Thursday after they announced the cancellation of next year's grand prix.
The French Grand Prix website (www.gpfrancef1.com) said on Wednesday that the French Motorsport Federation (FFSA) had scrapped next year's race for economic reasons and would refund all ticket purchases.
The FFSA had said earlier that it would no longer promote and fund the race, scheduled for the rural Magny-Cours circuit on June 28.
An International Automobile Federation (FIA) spokesman said that the world body had yet to be officially notified, however.
"The FIA secretary general has written to the president of the FFSA today to seek an urgent clarification of the situation of the French Grand Prix," he said.
"Up until today we have heard nothing and we are gravely concerned."
The 2009 championship has gone from 19 races to 17 in the space of 10 days, with Canada omitted from the calendar drawn up by Formula One supremo Bernie Ecclestone and published by the FIA on Oct 7.
The absence of both Canada and France next year leaves North America without a race for the first time in 50 years and also strips the calendar of one of the sport's founding nations. Only once since 1950 has France not been on the calendar.
