Christian campaigners have warned of 'outrage' over plans in Scotland that could allow adults and children to change their gender so that legally they are neither male nor female.

The reaction came after the SNP-led Scottish government unveiled proposals to create a 'non-binary' gender for people who do not identify as a man or woman and to make it legal to 'self-declare' which gender they want to be.

The plans mean that people in Scotland could change their legal status to male, female or 'non-binary' without any medical diagnosis or treatment, and potentially switch more than once.

Although a consultation paper stated that ministers favour setting a minimum age of 16 for people wanting to change their gender, one of the options under consideration would mean that pre-pubescent children could also make an application.

According to the Telegraph, the document noted that the law around parentage and marriage must be changed to 'clearly include non-binary people'. The criminal law may also have to be overhauled 'to ensure that any remaining gender specific offences can be committed by people of all legal sexes'.

The paper recognised that the UK Government would have to agree to change UK passports and driving licences to include a non-binary gender option and there was no guarantee that other countries would recognise the validity of the move.

It is estimated that there are more than 10,000 people in Scotland are transgender, and they do not need to have undergone any surgery or to have taken any drugs to change their bodies to be classified as such.

Angela Constance, the SNP's Equalities Minister, said: 'Scotland rightly has a reputation as one of the most progressive countries in relation to LGBTI legal and human rights equality in Europe – but we need to do more to progress equality for trans people.

'By holding a full and wide ranging consultation we can make sure that our law is fit for purpose and in line with international best practice.

'This is a vital conversation and one which will ensure transgender and non-binary people in Scotland are treated with dignity, fairness and respect.'

But Simon Calvert, the deputy director of the Christian Institute, told Christian Today: 'Politicians must stop and ask themselves if jumping on this bandwagon is really helping children. The more trans politics grips our culture, the more young people are being rushed into damaging hormone therapy and mutilating surgery by people motivated more by political posturing than the best interests of children.

'We are seeing more and more cases of young people experiencing profound regret at the damage done to their bodies and mental health by being placed on a conveyor belt to trans-identity simply for questioning their gender. But because trans politics depends on silencing dissent, their voices are rarely heard. Where are the Scottish politicians standing up for these kids?

'If this proposal by the Scottish Government means freezing out parents from one of the most life-changing and controversial decisions of their children's lives then there will be outrage.'