Thousands of farmers in Ireland and France protested on Saturday against the European Union's trade deal with the South American bloc Mercosur, a day after EU states approved the treaty despite opposition from some members.

The agreement is widely opposed by farmers for fear it will result in an influx of an extra 99,000 tonnes of cheap beef from South America, disrupting European agriculture.

In central Ireland, tractors streamed into the roads of Athlone for a demonstration, displaying signs including "Stop EU-Mercosur" and with the European Union flag emblazoned with the words "sell out".

"We have good quality Irish beef and and good standards here, and they don't have the same standards in South American countries," said Trisha Chatterton, a 50-year-old farmer. "There is not a lot of traceability on their beef."

In France, police on Saturday ejected farmers occupying a fuel depot near Bordeaux in the south-west. Later in the day other farmers tried to block road traffic to the port of Le Havre in the north-west. Two highways remained blocked Saturday in the south-west of France, farmer unions said.

Farmers on Friday also marched in Poland and blocked roads in France and Belgium as the EU gave the green light to the trade deal.

The deal, more than 25 years in the making, would create one of the world's largest free-trade areas, boosting commerce between the 27-nation EU and the Mercosur bloc comprising Brazil, Paraguay, Argentina and Uruguay.

The Mercosur deal still has to be approved by a majority of MEPs in the European Parliament in the coming months, where voting coalitions have become more volatile and unpredictable. (AFP)