David Coulthard's hopes of returning to the Red Bull
cockpit for a demonstration run in Austin, United States have been scuppered after the team ran into difficulties with city officials.
The Scot, who started 72 races for Red Bull
and is still listed as their test driver in between duties competing in the DTM and providing commentary for BBC's F1 coverage, was due to drive the car as a means of building interest for the city's inaugural grand prix next year.
However, problems securing a filming permit have forced Red Bull
to at least postpone the event.
"Due to feasibility, a formal Formula One show car demonstration that is open to the public will not be executed this week," a statement read. "Red Bull is excited about the upcoming US Grand Prix ... and eager to drive awareness of the race and the sport in general to a broad audience."