The Austrian post office designed the stamp to mark the 70th birthday of the Tibetan leader in 2005, but the stamp did not go into large-scale production.

"There were only a few test prints made by hand, because a new color was being tested," a spokesman for the Austrian post office told German news agency dpa.

The Austrian post office denied reports that political pressure from China had prevented the stamps from going into production. "Many designs are tested and not pursued," the spokesman said.

Auctioneers Felzmann maintain there are only 30 of the stamps in existence. The stamp had never before been offered at auction, they said. The starting price for Thursday's auction was put at 4,000 euros ($6,200).