France's total immigration population is about five million

New Immigration Minister Brice Hortefeux said a family with two children would be paid 6,000 euros (£4,068) to return to their country.

In 2005-2006, a similar scheme was taken up by some 3,000 families.

France is home to about two million immigrants from north and sub-Saharan Africa, according to a 2004 census.

"We must increase this measure to help voluntarily return. I am very clearly committed to doing that," Mr Hortefeux told France's RFI radio.

Mr Hortefeux last week was named immigration minister by newly-elected President Nicolas Sarkozy.

Mr Sarkozy has warned that France "is exasperated by uncontrolled immigration".

France was hit by a series of riots in the immigrant-heavy suburbs in 2005.