Farm unions and the Spanish government have once again appealed to the EU after protesting French farmers took control of two Spanish lorries and dumped their loads this week.

Lorries carrying wine from Spain were stopped by farmers at a toll station near the border. Farmers then painted the trucks and emptied their loads into the roadway. On Monday, Spanish farm union COAG referred to the incident as a “violent episode.” The union condemned the “passivity” of the French government and called on EU authorities to intervene to see that farmers and the national government honour EU treaties which guarantee free movement of goods between states in the bloc.

COAG is pushing for sanctions against the French government after this latest incident, which occurred on the A-9 motorway in the Pyrénées-Orientales department of France on Monday. COAG claims that the dumping happened within sight of TV cameras and French gendarmes (military police), who allowed the attack to go ahead.

After the union demanded that the Spanish agriculture ministry make a formal complaint to the French government on Monday, Spain’s ministers of agriculture and foreign affairs confirmed that they had informed their French counterparts and petitioned the EU Commission a day later.

French farmers blockading the road on Sunday claimed that they were acting in response to growing imports from Spain, which they said are undercutting prices paid to French producers - by about €30-40 (between £24 and £32) per hundred litres in the case of wine, according to the protestors.

However, COAG’s secretary general Miguel Blanco said, "These actions are intolerable. Spanish farmers are suffering under the same price crisis that’s affecting the French producers. The real culprits here are the large retail chains - mainly French - who abuse their dominant position in the market to impose ruinous prices on farmers.”

Monday’s hijack was not a new tactic employed by the protesting farmers; a string of such incidents last year reached an apparent peak in July. During nationwide protests in late July, Scottish hauliers transporting fish to the Highlands were diverted and trapped by around 200 farmers protesting in Brittany, who unloaded then destroyed their cargo of fish worth around £200,000. The drivers claimed that the farmers had scored an own-goal, and that the fish had been landed by a French trawler.