Karlsruhe - A German court on Tuesday quashed the hopes of a group of naturists who wanted to cycle along the Rhine River wearing nothing more than a smile.

Cycling in the nude, the Karlsruhe court ruled, is "highly inconvenient".

The group of 12 naturists were planning to cycle along the Rhine in the state of Baden-Wuerttemberg on Saturday as part of what they were dubbing "World Nude Cycling Day".

The court upheld an earlier decision from the local authorities to ban the ride.

It said that cycling in the nude contravened the unwritten rules of public decency.

While there was widespread acceptance of naturism on beaches, nude cyclists could offend people who were not expecting to see them, the judges said.