Spain's Catholic Church launched a campaign against stem cell research and abortion yesterday as the government considers easing restrictions on research with embryos.

Using the slogan "We were all embryos once", the Church will distribute millions of leaflets illustrated with pictures of a smiling family and advocating the rights of embryos.

Spain's Socialist government passed legislation allowing research on stem cells from embryos late last year and is now looking at a new bill to give researchers more leeway. It expects to pass another set of regulations later this year.

"Can one experiment on human beings... when that experiment brings the death of that human being? Can we eliminate a human being to benefit another? The Church's position is clear: 'no'," Secretary General of the Bishops' Conference Juan Antonio Martinez Camino told a news conference. While 95 per cent of Spaniards are nominally Catholic, only about a fifth practise and liberal attitudes are dominant.

The Church campaign comes after months of criticism of the government by the Church, angered by recent laws to make divorce easier and make Spain only the third country to legalise gay marriage.

The Socialists - who took over from the pro-church Popular Party last year - have also said they will consider making abortion easier to obtain.

Other Catholic EU countries such as Italy and Ireland oppose stem cell research although the European Union funds it. Scientists say stem cell research could yield cures for diseases such as Alzheimer's.

Stem cells are master cells which have the potential to grow into any human cell.