Motorsport chiefs raised the stakes in Formula One's row with the European Union over tobacco sponsorship by threatening to take the sport out of Europe.

Max Mosley, president of motorsport's governing body, has warned the European Commission that the sport will leave the EU if it refuses to back down on plans to ban tobacco sponsorship in 2005.

The International Automobile Federation (FIA) president has written to the commission outlining motorsport's "grave concern and dismay" over the ban.

The FIA, which met in Monte Carlo on Friday, has been campaigning for a worldwide ban on tobacco sponsorship in F1 by the end of 2006.

There were rumours that the FIA would scrap that plan but it has decided to keep October 2006 as its deadline for banning tobacco advertising.

"By choosing a date earlier than the world date, the EU will now force teams to seek events outside the EU during part of 2005 and all of 2006 in order to observe contracts which do not expire until the end of 2006," Mosley said.

"Such events will inevitably themselves seek long-term contracts and, of course, allow tobacco sponsorship."

Belgium has already been booted off next season's calendar because of a row over plans to introduce a tobacco ban in the country in 2003.

Ten of next season's 16 races will take place in Europe, but several would come under threat from the likes of Turkey and Russia should tobacco sponsorship not be allowed to continue.

Logos from the various tobacco companies will still be beamed into homes via television coverage from races that have replaced European venues.

Around half of the F1 grid - including Ferrari, Renault and McLaren - is still heavily reliant on tobacco advertising to the tune of hundreds of millions of pounds per season.