Formula One will have fewer than 20 races in 2006 despite the FIA releasing a list with that number of dates on it, according to supremo Bernie Ecclestone.
"I blocked off 20 dates but we can change some around," he told BBC Radio Five Live at the French Grand Prix.
"It won't be 20, I can assure you. 18, 19, 17 - who knows."
This year's championship is already the biggest in Formula One's 55-year history with 19 races and several team bosses have said that is too many.
The calendar is drawn up by Ecclestone but has to be approved by the FIA - the sport's governing body.
Mexico had been tipped to appear on the calendar next year at a new circuit in Cancun, but Ecclestone appeared to cast doubt on that.
"I don't know about Mexico, I haven't been there for a long time," he said.
But Ecclestone is working on keeping the USA on the calendar despite the June fiasco at Indianapolis where only six cars competed.