A French court has jailed Marie-Helene Martinez and her husband Jean-Paul Steijns for 20 and 10 years respectively for killing their two children with poisoned cannelloni.

The sentences was less than the 30 years asked for by the public prosecutor and relatives of the murdered children, eight-year-old Melissa and seven-year-old Jason, reacted angrily in court.

"Die, die in prison!" the children's aunt shouted at Martinez, 29, who collapsed in tears when the sentence was read out in the southern town of Aix-en-Provence.

Steijns, 39, remained impassive throughout the trial.

"They should have got life. Ten years is nothing for a mother who poisons her children," shouted another relative, as the children's grandmother wept silently.

Martinez's lawyer said he would appeal, even though the move was "an enormous risk".

Steijns' lawyer said he accepted the sentence.

At the start of the trial, Martinez had denied killing the two children a day before she gave birth to a still-born baby whose rotting body was later found on her balcony.

The couple decided in 2005 to poison their children, believing they would be better able to pull themselves out of debt without them, the court heard.

Steijns, who is not the biological father of the children, told the court his wife persuaded him to carry out the crime when the couple risked losing their flat in nearby Marseille after several months of defaulting on rent.

But Fernandez told the jury that the couple were both guilty as they had jointly decided to poison their children with the pasta.

On the night of September 18, 2005, Melissa and Jason complained that the meat-stuffed cannelloni served by their parents tasted bitter and they went to bed that night without finishing their plates, Le Parisien newspaper reported.

They died that night and the bodies, hidden in a car boot, were discovered a month later when Steijns confessed to police.

Police also found the decomposed body of a newborn baby lying on the balcony of their Marseille apartment in 2005 but the couple is not on trial in that case.

Investigators have been unable to establish the circumstances of the death, given the advanced stage of the body's decomposition.

- AFP