Education Secretary Damian Hinds told MPs in parliament on Thursday that children should be able to request sex education in at least one of the three terms before their 16th birthday.
James Mildred, spokesperson for Christian charity CARE, told Premier why he thinks it is problematic.
"This is about who is ultimately best placed to have responsibility for the education. And it is not politicians - it's parents who have the ultimate responsibility for educating their children."
The proposed change is part of new draft guidelines on the teaching of sex education in England's schools.
The guidelines - which will become compulsory from 2020, are now open to consultation.
Defending the decision Hinds said in the Commons: "A right for parents to withdraw their child up to 18 years of age is no longer compatible with English case law nor with the European Convention on Human Rights.
"It's also clear that allowing parents to withdraw their child up to age 16 would not allow the child to opt into sex education before the legal age of consent."
The new wider guidelines people are being encouraged to share their views on will include mental wellbeing; consent; keeping safe online; physical health and fitness and LGBT issues.
Mildred told Premier the new plans are not respectful of Christian parents.
"We must respect the fact that there are parents with strong deeply held religious convictions. Think of especially of Christian parents who might like the right to withdraw their child. That right should be respected.
"More crucially, there must be continual dialogue between parents and schools. The best way of providing a holistic and affective relationships and sex education is not bypass the parents, not to create this arbitrary age at which point a child can veto their parent's decisions but to involve the parents from the beginning.
"There are some parents who will disagree with the content of the relationship and sex education that the government is proposing."
Listen to James Mildred speaking with Premier's Tola Mbakwe:
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