Paedophilia is a “sexual orientation” like being straight or gay, according to a criminal psychologist.

The idea that sexual attraction to children is an “orientation” is highly controversial as it suggests that offenders cannot change.

But, writing on the Reddit networking website, the psychologist said it was possible to treat child sex abusers on “the understanding that the attraction may always remain”.

The psychologist set up the “ask me anything” thread on Reddit. Their identity was not revealed but was verified by the website.

Asked “can paedophiles actually change?”, the expert wrote: “I believe Paedophilic Disorder is a sexual orientation with individual that are attracted to child features. In other words, an individual with paedophilia has the same ingrained attraction that a heterosexual female may feel towards a male, or a homosexual feels towards their same gender.

“With that being said, it needs to be said that sexuality is more of a spectrum than a finite category. We know that heterosexuals may engage in homosexual behaviour, and deny they are bisexual or homosexual.

“We know that individuals with paedophilia may engage in sexual behaviour with adults. For some, they may use this as a cognitive distortion to explain away their sexualisation of prepubescent children.”

However the psychologist stressed in a later edit that they had not mean to imply paedophiles could not be treated – to an extent.

“Treatment, to me, isn’t about modifying the orientation per se, but getting the individual to find more appropriate behaviours to engage in,” they wrote.

“An individual can have paedophilic interests without ever acting on these behaviourally. However, as I am working with criminal offenders, my experience is entirely weighted to those who have engaged in this behaviourally.”

The psychiatrist said they focused on three main areas when trying to treat a child sex abuser: “One, do you understand who can and can't provide consent? How will you go through and identify this? Two, can you identify the risks or situations which would increase when you engage in sexual activity with someone who can't provide consent? How can you avoid these or limit them? Three, what can you focus on positive in your life which can replace or mitigate when you may be most likely to offend? What are some things you can do which are adaptive and help you in the long run?”

In May 2015, research from the National Crime Agency suggested 250,000 men in the UK could be considered "true paedophiles" - adults who are attracted to pre-pubescent girls less than 12 years old.

Talking to The Independent in the wake of the research, one psychologist working said they should be treated as victims rather than offenders.

“It is a disease, it is a trait, it is not a choice. They haven’t chosen to change, but they can learn how to live responsibly with their sexual desires," Petya Schuhmann, who works with a scheme in Germany called Project Dunkelfeld, which allows individuals to anonymously contact therapists who help them control their sexual urges towards children.

Last year, a self-confessed paedophile, Todd Nickerson, a freelance graphic designer from Tennessee, caused uproar after writing an article asking people to be understanding of his "sexual orientation".

Called I'm a paedophile, you're the monsters, the piece explained how he believed his molestation as a child was the reason he is now sexually attracted to young girls. He also mentioned his membership of the "Virtuous Paedophiles" forum - an online community of paedohpiles who have vowed never to act on their sexual urges.

In July 2010, the Harvard Mental Health Letter of July 2010 stated that "paedophilia is a sexual orientation and unlikely to change. Treatment aims to enable someone to resist acting on his sexual urges".

The idea of treating paedophilia as a disease has long been controversial.