Two-time Tour de France champion Lance Armstrong and US Olympic cycling team-mate Tyler Hamilton received slight injuries when they were knocked down by a car while training in Nice.

Armstrong, who suffered the brunt of the impact was heavily bruised, while Hamilton (29), received lesser injuries, US Postal team director Johan Bruyneel said.

Bruyneel said Armstrong would have to rest for an indefinite period, but the 28-year-old was nevertheless expected to compete for the US in the Sydney Olympics, Bruyneel added.

The American was training with team-mates Hamilton and Frankie Andreu on a little used back road in the south of France.