PARIS—France is preparing to deport hundreds of foreign Gypsies as part of a drive to clamp down on lawbreaking by Roma, Interior Minister Brice Hortefeux said Tuesday.

The deportations, scheduled to start Thursday, follow the dismantling of 51 illegal camps—set up by Roma of eastern origin and by other Gypsies, including French citizens—over the past three weeks. Around 700 of the people expelled from their camps who were staying in France illegally will be flown home to Central and Eastern Europe, he said.

"We are not stigmatizing a community, but making people respect the law," Mr. Hortefeux said in a speech in Toulon, southern France.

A Roma woman leaves a makeshift shelter on Tuesday that was built after French police seized her family's trailer two weeks ago from an illegal camp in Roubaix, northern France. Rueters

Around 15,000 Gypsies in France are Roma from Eastern Europe, in particular Romania. Because the European Union guarantees freedom of movement, they can travel to France—but can settle there only if they can support themselves. After three months in France, they must leave unless they can prove that they are working or studying and that they have sufficient funds and health care.

The French government is interviewing the Roma to determine where they are from. It plans to put those who aren't allowed to remain legally in France on flights home, and is offering them €300 (about $390) per adult and €100 per child as "aid for a humanitarian return."

To prevent them from returning and claiming such payments again, the government plans to collect biometric data on those who are deported. Most of the foreign Roma don't appear to be resisting deportation.

Officials at the Romanian Embassy in Paris couldn't be reached to comment.

Dismantling the illegal camps is part of a wider law-and-order push by President Nicolas Sarkozy following a number of skirmishes this summer. The campaign has led to charges that he is engaging in a populist ploy to distract from a number of political setbacks. His ruling UMP party did badly in regional elections in March. In July, a prosecutor launched a probe into links between Mr. Sarkozy and Liliane Bettencourt, heiress to the founder of French cosmetics group L'Oréal SA. Mr. Sarkozy denied that Ms. Bettencourt had illegally financed his 2007 presidential campaign—but he was hurt by the perception of links to Europe's richest woman, who has also admitted evading taxes. And although France's economy improved, growing 0.6% in the second quarter, the latest unemployment figure remained stubbornly high at 9.5%.

In mid-July, young people living in housing projects in Grenoble, southeast France, torched cars and fired on police following the shooting death of a suspect in a casino robbery. Separately, aIn July, after police in Saint-Aignan, in central France, shot dead a 22-year-old Gypsy for failing to stop at a roadblock, Gypsies armed with hatchets and iron bars felled trees and traffic lights, torched cars and attacked a bakery and a police station.

Two weeks later, on July 28, Mr. Sarkozy said the government would dismantle illegal sites used by Gypsies. He also proposed stripping French citizenship from people of foreign origin who were convicted of trying to kill police or other public officials. Separately, a member of Mr. Sarkozy's ruling UMP party has proposed that parents of delinquent children be imprisoned for up to two years.

The law-and-order drive has played well in opinion polls. Mr. Sarkozy's approval rating was up two percentage points at 34% in early August from July, according to pollster CSA. In a separate survey, 80% of respondents said they were in favor of the proposal to strip people of French nationality if they were convicted of attempts on the lives of French officials, while 79% agreed with dismantling illegal Gypsy camps.

Mr. Sarkozy launched the campaign "to hide his political weakness," said Daniel Cohn-Bendit, co-leader of the European Parliament's Green grouping, in an interview in Monday's Le Monde newspaper.

But the moves could backfire if the French public tires of Mr. Sarkozy's harsh tone. A UMP lawmaker who opposes the Gypsy expulsions, Jean-Pierre Grand, described them as rafles, using the French word for "roundups." The word is associated with the World War II roundup of Jews by French police on behalf of the occupying Nazis.

Immigration Minister Éric Besson, also of the UMP, countered that the implied comparison was unfair. "People are interviewed, their identity is verified and we offer them money to go back to their country of origin," he told radio station RTL on Tuesday. "I would like someone to explain the link with the roundups of World War II."

The issue is complicated by a lack of reliable information about the Gypsy groups. Many of those whose campsites have been closed are French, sometimes descended from Roma, a distinct ethnic group. The French government has traditionally taken a progressive approach toward them: Since 1990, larger French towns have been obliged to provide them with campsites equipped with electricity and water supplies.

However, some cities don't provide adequate accommodation, the Gypsies say. Sometimes they settle illegally. Last weekend Gypsies blocked a bridge in the city of Bordeaux after they were refused the right to settle on a local sports field. Spokesmen for the group said two other options offered to them weren't suitable.

The recent decision to shut down camps and expel Gypsies who aren't French citizens is the first time the French government has pursued such a hard-line policy, says Robert Kushen, managing director of the Budapest-based European Roma Rights Centre. "It's a very draconian measure," he says. "It's not going to solve much."