The Vatican has defended the excommunication of those involved in helping a nine-year-old girl get an abortion in Brazil after she was allegedly raped by her stepfather.

Cardinal Giovanni Battista Re, the head of the Roman Catholic Church's Congregation for Bishops, told the Italian daily La Stampa over the weekend that the unborn twins the girl was carrying had the right to live.

"It is a sad case but the real problem is that the twins conceived were two innocent persons, who had the right to live and could not be eliminated," he said.

The senior cleric's comments come after Brazil's president, Luiz Inacio Lula da Silva, criticised Jose Cardoso Sobrinho, the Brazilian archbishop who excommunicated the girl's mother and the doctors involved in aborting the baby, but not the stepfather who allegedly raped the girl.

Lula said that as a Catholic, he deeply regretted the archbishop's "conservative attitude".

"It is not possible to allow a little girl raped by her stepfather to have that child because it could put her life at risk," he said.

"I believe that in this sense, medicine is more correct than the church."

But the cardinal said "life must always be protected, the attack on the Brazilian church is unjustified".

'Worse than rape'

The nine-year-old from the northeastern state of Pernambuco in the world's largest Roman Catholic nation, was found to be four months pregnant last week after allegedly being raped by her stepfather.

Doctors said they decided to terminate the pregnancy because the girl's life was in danger due to her young age, and because she was carrying twins.

But Sobrinho, the archbishop of Olinda and Recife, in declaring the excommunication, said the abortion went against "the law of God".

The stepfather was not excommunicated because the church said that his action, although deplorable, was not as bad as ending the life of an unborn child.

"It is clear that he committed a very serious sin, but worse than this is the abortion," Sobrinho said.

Under church law, excommunication is automatic for followers who have, perform or help procure an abortion.