Britain’s national academy of science urged the United Nations on Monday to ignore a call by President Bush to ban all forms of human cloning.

The Royal Society said the United States should be allowed to decide whether therapeutic cloning, creating embryos as a source of stem cells to cure diseases, is prohibited within its own borders.

“But other countries, including the UK, have now passed legislation to allow carefully regulated therapeutic cloning while introducing a ban on reproductive cloning,” Lord May of Oxford, the president of the society said in a statement.

Last month in a speech to the United Nations Bush called for all countries to support a ban on therapeutic and human reproductive cloning proposed by Costa Rica.

May believes nations should back a Belgian proposal when the U.N. General Assembly votes on the issue later this month. The Belgian plan would outlaw human reproductive cloning but allow countries to make their own decision on therapeutic cloning.

“If this proposal was successful the United States and others would be still be free to ban all human cloning but countries that see the promise offered by therapeutic cloning can still carry out research,” May explained.

Therapeutic cloning is thought to hold potential for new treatments for illnesses such as Alzheimer’s, Parkinson’s and heart disease, but it is a controversial area of research because it involves the creation and destruction of early embryos.

The Royal Society argues that countries that allow regulated therapeutic cloning would not sign up to a convention supporting a total ban on cloning.

Although member nations would not be compelled to support a treaty banning all forms of human cloning, the society said it would place a major obstacle in the way of stem cell research.

“The US government’s approach at the UN appears more designed to influence domestic legislation, where attempts to introduce a total ban have so far failed, at the expense of a workable international ban on reproductive cloning,” said May.

“Indeed, the US has not yet outlawed reproductive cloning itself,” he added.