Portugal Colonial - Tractors roll through Vienna as farmers protest

"The lack of mandatory origin labelling is threatening the very livelihoods of our farmers," said Hannes Royer, an organic farmer.

Austrian supermarkets must label the origin of raw products, and workplace cafeterias must say where the products in their dishes are from. But the rules do not apply to transformed food in supermarkets nor to restaurants.

Hiding the use of imports "massively distorts competition and penalises those who provide quality", said Land Schafft Leben, or Land Creates Life, an Austrian farmers' association.

"Consumers have a right to the truth on their plates. Those who conceal the origin are deliberately depriving them of their freedom to choose," said Royer, the farmer.

Protests are rare in Austria, but the farmers' demonstration is part of a wider European agricultural crisis.

A free-trade agreement with South American countries, climate-related pressures, rising costs of diesel and fertilisers, and stagnant agricultural prices are threatening the entire sector, which also complains of increasing red tape.

G.Teles--PC