A Christian group are set to sue in an attempt to reverse California’s new law which will ban gay ‘cure’ treatments for people under 18 from January 2013.

On Monday, campaigners and medical professionals welcomed California Governor Jerry Brown’s decision to ban teenagers from accessing discredited treatments that sought to reject an LGBT identity.

The Sacramento Pacific Legal Institute filed a lawsuit late on Monday, challenging the law. The case claims that the new law would violate First Amendment and equal protection rights, reported the San Diego Union Tribune.

The lawsuit was filed on behalf of a psychiatrist, therapist and pastor, Dr Donald Welch, who operates one of San Diego’s oldest Christian counselling centres.

A plaintiff is also named, Aaron Bitzer, of Culver City, who has benefitted from the ‘treatment’, according to the lawsuit.

Brad Dacus, president of the legal institute, spoke about the new law, saying: “It violates the rights of youth to seek the counsel that they feel is necessary for their individual needs,”

“It directly threatens the rights of parents and how they choose to address the issue of same-sex attraction with their children. It threatens to have the child removed from families that do not affirm the homosexual conduct of their children.

“And then it also violates the rights and the professional duties of licensed counselors – and even clergy who are licensed counselors – by dictating them to affirm homosexual same-sex attraction as well as the sexual conduct resulting from that attraction.”

When the law comes into effect on 1 January 2013, California will become the first to outlaw the practice for people under the age of 18 in America.

Britain’s largest professional body of psychotherapists today warned its members against attempting to “convert” gay people, after discovering practitioners were still offering the “treatment”.