The leader of the Catholic Church in Australia, Cardinal George Pell, says he regrets that a bill overturning a ban on therapeutic cloning has passed the lower house of NSW Parliament.



In a rare conscience vote, the bill allowing stem cell research, also known as somatic cell nuclear transfer, was today approved by the lower house 65 votes to 26.



To become law, the bill must be debated and passed by the state's upper house. The Minister for Science and Medical Research, Verity Firth, said this would not happen until Parliament's next session.



Cardinal Pell said he remained hopeful the bill would be defeated in the upper house.



"The Catholic Church supports adult stem cell research, especially for health cures, and remains opposed to the destruction of human life," Cardinal Pell said in a statement.



"In our democracy, parliament legislates. I regret the vote of the NSW Legislative Assembly on cloning and hope that the Legislative Council will be better informed."



The cardinal said the Sydney Catholic Life Office was prepared to offer information to "any person who wishes to understand the pro-life position better".

Cardinal Pell has come under attack by MPs after he said Catholic politicians who voted in favour of the bill could expect consequences for their place in the life of the church.



Emergency Services Minister Nathan Rees said yesterday the cardinal should apologise to Catholic MPs or risk comparisons to controversial Muslim leader Sheik Taj Aldin al-hilali.



A number of high profile MPs, including Premier Morris Iemma and his deputy John Watkins, are Catholic.



Both Mr Iemma and Mr Watkins voted in favour of the bill.



The NSW legislation mirrors that passed by the Commonwealth in December last year and is similar to a bill passed by Victoria's Parliament in May.



Scientists hope their work with stem cells will yield significant medical breakthroughs within a decade.

Church leaders are allowed to express views: Howard



Cardinal Pell and Perth Archbishop Barry Hickey are entitled to express their views on stem cell research, Prime Minister John Howard said.



Archbishop Hickey came under fire after he reportedly said Catholics who did not condemn the cloning of human embryos for medical research were acting against the teachings of the Catholic faith and may face excommunication.



Mr Howard today said he did not believe either man was trying to direct MPs on political matters.



"I think it's exaggerating things to say that,'' he told ABC radio. "I think that Cardinal Pell and Archbishop Hickey are both church leaders; they are entitled to express their views and I respect both of them."



Mr Howard said church leaders had not directed his decision to vote against overturning the ban on therapeutic cloning when legislation was before Federal Parliament last year.



The "no" voters were: