"Whatever our religious creed or political conviction, abortion on this scale can only be a source of distress and profound anguish for us all...Abortion robs everyone of their future. Individually and as a society we believe we have another choice: to give birth to life."
Anti-abortion campaign groups have made desperate pleas for the upper limit for abortions to be cut to 20 weeks, or even closer to the levels of some European countries which have set the limit as low as 14 weeks.
However, the British Medical Association says the number of babies surviving at 24 weeks is still "extremely small".
The Royal College of Obstetricians and Gynaecologists, and the Royal College of Nursing also maintain that the upper time limit for abortions should remain at 24 weeks.
The British Health Minister, Ms Primarolo was giving evidence this morning to the House of Commons Science and Technology Committee, which is looking at medical advances since the Abortion Act was passed in 1967 - but it has stated that it would make its assessment without any consideration of ethical or moral issues associated with abortion time limits.
In their letter, the cardinals set out their plans for reducing the number of abortions carried out in the UK every year.
The letter read: "Whilst upholding the principle of the sacredness of human life, it is both licit and important for those in public life who oppose abortion on principle to work and vote for achievable incremental improvement to what is an unjust law."
Speaking on the Today programme on Radio 4 yesterday morning, Cardinal Murphy-O'Connor said, "I think there is such a thing as a gradual change and there are many politicians and the people who they represent who would be happy for a gradual change in the law."
