Health Minister Norman Lamb has written to NHS England asking for assurances that GPs are not referring gay people for conversion therapy.

Mr Lamb told The Guardian that gay-to-straight conversion therapy was “based on the completely false premise that there is something wrong with you if you happen to be gay”.

“I certainly want to do what I can, as a Liberal Democrat, to eradicate this,” he said.

“I don’t think there should be referrals to professionals in the NHS. I haven’t seen evidence of referrals, but in a vast system [such as the NHS] one imagines that could happen. So we have to be clear about the inappropriateness of that.

“There are steps we can take to make sure it has no place in the NHS. We can also send a clear signal that health professionals within the NHS should not be referring people – it would be entirely wrong.”

Last week, a cross-party group of 15 MPs sent a joint letter to the Lib Dem minister.

The letter, initiated by Shadow Home Office Minister Diana Johnson, urged ministers to investigate potential NHS links with conversion therapists and explore the regulation of counselling and psychotherapy.

Campaigners warn at present there is no legal requirement preventing psychotherapists who believe it’s possible to ‘cure’ a person’s sexual orientation from being able to operate.

A 2009 survey of 1,328 accredited mental health professionals showed 17% of practitioners readily admitted to having assisted at least one client to reduce their same-sex attraction.

Some 35% of patients therapists described were referred to them for treatment by general practitioners, and 40% were reported as actually being treated inside an NHS practice.

In response to the letter, the Department of Health reaffirmed that it had no intention of introducing statutory regulation for psychotherapists.

Labour MP Diana Johnson accused Mr Lamb of “completely” ignoring the issues.

She said: “Conversion therapy is a very real and present danger in Britain.

“More than just a problem amongst religious fundamentalists, it’s an issue for the NHS and professional sector.”