The UK’s governing body for psychiatry has been asked to follow the lead of their American counterpart and advise its members not to refer clients who are confused about their sexuality to therapies that claim to change their sexual orientation.

Earlier this year, research found that one in six therapists in Britain had tried to turn gay people straight.

The American Psychological Association declassified homosexuality as a mental disorder in 1973 and earlier this week it produced a study that concluded homosexuality cannot be cured.

Judith Glassgold, chair of the task force assigned to the study, said: “There is insufficient evidence to support the use of psychological interventions to change sexual orientation.”

In a letter to Professor Dinash Bhugra, the president of the Royal College of Psychiatrists, the National Secular Society, wrote:

“The American Psychological Association concluded, after analysing 83 studies, that these therapies do not work and can, in some circumstances, induce depression and suicidal impulses.

“In the light of this, we were alarmed to read in a report in the Guardian earlier this year that a significant number of psychiatrists and psychologists in Britain are still offering to help gay people change their sexual orientation.

“With this in mind, we would like to suggest that the Royal College of Psychiatrists and the British Psychological Society consider issuing an advisory to their own members

“Enough research has now been done in this area to show that the therapies are not only ineffective, but often lead to further problems.

“Much of the pressure for the continuation of these therapies comes from evangelical religious sources, which have a theological objection to homosexuality.

“The American Psychological Association recommends that its members either encourage devout individuals who put their religion before their sexual needs to embrace celibacy, or to change their religious allegiance to another church that is more accepting.

“The idea that they should be “converted” to heterosexuality is more of a theological demand than a scientific reality.

“Attempting to do this can, as the APA study suggests, create a sense of fear in individuals when it does not work.”