The annual June beanfeast, which is about to celebrate its 50th anniversary, could be hit by a drop in attendees.
At the same time, the festival, renowned for its displays of conspicuous consumption, is likely to be a more low-key event than usual as communications groups cut back on their entertaining.
Roger Hatchuel, the festival chairman, feared American attendance might be down, following President Chirac's stance on the war.
Those agencies that do attend insist they will be keeping a tight hold on the purse strings. Ogilvy & Mather said it was sending only a "handful" of delegates, while its WPP stablemate, J. Walter Thompson, is cancelling its usual cocktail party.
Gary Goldsmith, the chairman and chief creative officer of Lowe North America, said: "The fear of travel, the French thing, the money thing. All these factors combine. It's got to have some impact."