From an AMA Pro Racing press release:

TEAM USA WITHDRAWS FROM MOTOCROSS DES NATIONS, TRIAL DES NATIONS

PICKERINGTON, Ohio — In the wake of the week’s tragic events, the American Motorcyclist Association (AMA) and AMA Pro Racing have today withdrawn the Team USA entries from the Sept. 30 Motocross des Nations in Namur, Belgium, and the Sept. 23 Trial des Nations in La Bresse, France.

The decision was made after consulting with the riders and team managers involved and assessing the logistics and security issues involved in international travel for high-profile American athletes.

In a letter to the Federation Internationale de Motocyclisme (FIM), world governing body for motorcycle sport, AMA President Robert Rasor expressed gratitude for the outpouring of sympathy and support received by AMA from other member federations of the FIM. Rasor also expressed support of the FIM’s decision to go forward with the events.

Earlier in the day, the FIM confirmed that the Trial des Nations and Motocross des Nations would be held as scheduled, but with muted victory podium activities and moments of silence to commemorate the tragedies of Sept. 11.

“Competing in these events, which are the equivalent of the Olympic games for motocross and observed trials riders, is a highlight of every season for American motorcyclists,” Rasor commented. “It’s with great reluctance that we have withdrawn Team USA, but it seems the most prudent course of action.

“Team USA was the defending champion of the Motocross des Nations, and the American Trial des Nations team had qualified for the top flight of that prestigious event for the first time. We need to thank Motocross des Nations Team Manager Roger DeCoster, Trial des Nations Team Manager Martin Belair and all of our riders for their help and support,” Rasor said. “It’s unfortunate that we will not be able to compete, but any disappointment is insignificant in light of current events. We look forward to renewing our friendly rivalries in these and other FIM championships in coming years.”