Criticism mounted Wednesday of France's move to expel hundreds of Roma gypsies, with Romania warning of a xenophobic reaction and the EU calling on France to obey migration rules.

The French government has said it will on Thursday begin expelling to Romania and Bulgaria around 700 Roma rounded up in a clampdown on members of the minority living illegally in France.

Romanian Foreign Minister Teodor Baconschi said on Wednesday he was worried about the risk of "xenophobic reactions".

"I am worried about the risks of populism and xenophobic reactions in a context of economic crisis", Baconschi said in an interview with the Romanian service of Radio France International (RFI Romania).

Seventy-nine Romanian Roma who agreed to a so-called "voluntary return procedure" will arrive in Bucharest on Thursday on a regular flight.

France intends to fly 132 more to Timisoara, in western Romania, and Bucharest on Friday and 160 on August 26, Valentin Mocanu, Romanian state secretary in charge of Roma reintegration, told AFP.

They will be granted 300 euros (385 dollars) for adults and 100 euros for minors.

About 10,000 Roma from Romania and Bulgaria returned to their countries using this "voluntary return" procedure last year but the flight planned on Thursday is the first since French President Nicolas Sarkozy launched a controversial crackdown on Roma, Gypsy and travellers communities.

Baconschi said he "hopes" that all legal procedures have been duly applied for these "expulsions".

The European Union's executive arm said Wednesday that France must abide by the bloc's freedom of movement rules when it expels Roma living illegally in the country.

The European Commission is following the situation "very attentively," a spokesman, Matthew Newman, said.

Most of the Roma who were sent to Romania last year returned to France afterwards as European citizens free to travel in the EU, officials admitted.

The French foreign ministry insisted that the measures being taken against the Roma were in line with European rules.

"The measures taken by the French authorities with regard to dismantling illegal camps fully conform with European rules and do not in any way affect the freedom of movement for EU citizens, as defined by treaties," foreign ministry spokesman Bernard Valero told AFP.

Valero said a European directive "expressly allows for restrictions on the right to move freely for reasons of public order, public security and public health."

Human rights groups and media in Bulgaria also criticized France's handling of the Roma question, though the foreign ministry in Sofia said it did not expect many Bulgarians to be affected.

Krassimir Kanev, head of rights watchdog the Helsinki Committee in Bulgaria, said he was "worried by the measure aimed at an ethnic group".

Ilona Tomova, a researcher specialising in the Roma at the Bulgarian Academy of Science, said she was "saddened that France, the symbol of democracy, was contributing to the stigmatisation of the Roma".

Bulgarian opposition newspaper Sega said Sofia and Bucharest had no way of stopping Roma moving across Europe, save for "a return to communism with the requirement of exit visas."

There are about 15,000 Gypsies and Roma of Eastern European origin in France.

The Roma community in Romania numbers 530,000 according to the national census or 2.5 million according to non-governmental organisations, who say that some do not declare themselves as Roma fearing discrimination.