Introducing a conversion therapy ban similar to that in the Australian state of Victoria could be "catastrophic", Christian campaigners have warned.

It follows reports that parents in Victoria have been left "distraught" at the prospect of being prosecuted if they do not affirm their child's desire to change gender. 

One mother of a gender dysphoric daughter said she feared being prosecuted simply for trying to find mental health support for her child.

The ban came into effect across Victoria in February and criminalises attempts to change or suppress a person's sexual orientation or gender identity.

Victoria's Change or Suppression (Conversion) Practices Prohibition Act 2021 carries penalties of up to 10 years in prison and a maximum fine of £100,000.

Official guidance extends the ban to "a parent refusing to support their child's request for medical treatment that will enable them to prevent physical changes from puberty that do not align with the child's gender identity".

UK supporters of a conversion therapy ban are calling on lawmakers here to copy the Victorian legislation but the Christian Institute has warned that this would lead to "Tavistock ideology enshrined in law" - a reference to the NHS gender clinic that is to close after it was strongly criticised in a review for prescribing puberty blockers to youngsters.

The Let Us Pray campaign, led by The Christian Institute, says the Victoria ban is a warning to legislators in Westminster, Holyrood and Stormont who are considering introducing similar laws here.

A legal opinion from Jason Coppel QC, obtained by The Christian Institute in 2021, warned that a conversion therapy ban in the UK could breach the rights of parents not to affirm their child's gender transition.

Simon Calvert, spokesperson for Let Us Pray, accused activists of "exploiting concerns about conversion therapy to criminalise people for having the 'wrong' opinions about LGBT issues".

He warned that people could be criminalised simply for disagreeing with transgender ideology.

"The Scottish Government and Government Ministers in Northern Ireland have committed to including trans in a ban. No 10 has said it does not want to, but MPs and Peers have pledged to amend the Bill to include it," said Mr Calvert.

"Parents of gender-confused children in Victoria are living in terror of being prosecuted for trying to protect their children from irreversible medical interventions.

"The Tavistock is rightly being closed down because of the terrible damage it has done to young people. The idea that Holyrood, Stormont or Westminster might enshrine Tavistock's 'affirmation-only' ideology into law is too awful to contemplate."