Spain has condemned attacks by French farmers against Spanish trucks carrying wine as part of a protest against falling food prices, saying the government had complained to Paris and the European Union.

In the latest of a string of angry protests, a group of French farmers stopped two Spanish tucks on Monday at the toll gate of Le Boulou in southern France near the border.

The farmers then dumped the wine the vehicles were transporting, according to the Spanish Federation of Freight Transportation (CETM).

The assault took place in front of television crews and French police who “allowed the demonstrators to act with impunity”, the CETM, which represents truckers, said in a statement.

Spain's foreign ministry said it “condemned the aggression suffered on Monday near Le Boulou by several trucks which were transporting Spanish wine”, adding that it informed the European Commission of what had happened.

“These events, which unfortunately occur regularly, are a cause of concern for the Spanish government, as they represent a flagrant violation of several basic principles of the European Union, such as the free circulation of goods between member states,” the statement added.

“Spain has already officially protested to French authorities, and urged them to adopt all necessary measures to guarantee the total security and free circulation of people and goods.”

French farmers have been furious over falling food prices, which they blame on foreign competition as well as supermarkets and distributors.

The farmers involved in Monday's protest complained that Spanish bulk wine sells for just €30-40 ($34-45) per hundred litres while French bulk wine costs 70-80 euros, Spanish newspaper El Pais reported on its website.

In July farmers stopped hundreds of lorries bringing produce from Germany, setting up checkpoints with around 1,000 people and tractors, while similar protests took place near the Spanish border.

Farmers ransacked trucks from Spain on a highway in the southwestern Haute-Garonne region, threatening to unload any meat or fruit bound for the French market, prompting another complaint from Spain's foreign ministry.

French farmers estimate that around 10 percent of farms in France – approximately 22,000 operations – are on the brink of bankruptcy with a combined debt of €1billion ($1.14 billion).

Dumping Spanish wine is not a new tactic by protesting farmers as this 2006 photo below shows.