Members of France's Roma, Gypsy and traveller minorities blocked a major highway outside Bordeaux on Sunday after hundreds of them were kicked out of an illegal campsite.

President Nicolas Sarkozy's government has in recent weeks launched a major and controversial crackdown on the travelling minorities, closing unauthorised camps and expelling foreign-born Gypsies from the country.

Sunday's blockade was the first major counter-protest by the groups, and more than 250 cars, trucks and caravans blocked the Bordeaux bypass and a bridge over the River Garonne in the southwest of the country.

Police and road safety officials said northbound traffic towards Paris was backed up for five kilometres (three miles) and southbound into Bordeaux for two kilometres, causing major disruption on a summer public holiday weekend.

The Gypsies were kicked out of a campsite in the town of Anglet, further south, earlier Sunday and had been forbidden from moving onto an exhibition ground nearer Bordeaux by municipal officials, police said.

Last month, following a clash between Gypsies and police in another region, Sarkozy announced a raft of new draconian security measures, including plans to dismantle 300 unauthorised campsites within three months.

Critics accused the French leader of stigmatising travelling minorities in a bid to recover votes lost to the anti-immigration far right in time for his re-election battle in 2012.

But opinion polls show most French voters approve of the measures.

There are estimated to be 15,000 Gypsies and Roma of eastern European origin in France. Some live in authorised encampments, and others have moved into squatter camps or abandoned buildings.

Last month, a group of French Gypsies rioted after one of their number was shot dead by police during a car chase in Saint-Aignan, central France.

Struggling in the opinion polls, and with his government and ruling party dogged by financial scandal, Sarkozy took the opportunity to launch a series of new severe security measures.

In addition to expulsions and the destruction of camps, a squad of tax inspectors has been set up to target what Interior Minister Brice Hortefeux called the owners of "caravans pulled by certain powerful cars".