MPs have questioned the practicality of government proposals to regulate supplementary religious schools in the UK, calling them oppressive.
The damning assessment came as MPs debated plans to regulate "out of settings" schools, after David Cameron pledged last year to close down madrasas – supplementary Islamic schools – preaching hatred to vulnerable children.
"Out of settings" schools apply to any institution providing education to children under the age of 19 that isn't a school, college, or registered childminder.
Criticism of the proposed clampdown has grown after it emerged that Christian Sunday schools could also face inspections.
However, in a letter sent to Conservative MP Sir Gerald Howarth, the prime minister said schools regulator Ofsted would only be given the extra powers to inspect schools "where children could be spending more than six to eight hours a week".
Speaking in Westminster Hall on Wednesday, Gavin Robinson, a DUP MP, said the measures were "completely unworkable" and said extremist preachers would simply reduce the number of hours they operate to escape government scrutiny.
"Which jihadist or fundamentalist would abide by the letter of the law?" Robinson asked. "Even if they are radicalised or militarised, are they not capable of stopping their radicalisation lessons at five hours and 59 minutes per week?"
Robinson told BuzzFeed News that the current proposals "verge on the oppressive".
"They certainly go against the 'big society'," he said. "They go against the opportunities for a positive society and they infringe against those who are doing good works in our society, and that's within the Christian, Jewish, Islamic, and non-faith beliefs."
Schools minister Nick Gibb told MPs the government was "committed to upholding the rights of parents wishing to educate their children in the tenets of their faith", adding that any monitoring of religious supplementary schools would be reasonable.
Gibb was forced to respond after MPs raised concerns that plans to regulate religious education in order to tackle extremism were heavy-handed and could lead to Ofsted becoming "the state regulator of religion".
Conservative MP Fiona Bruce warned MPs that the proposals could also be "in breach of the UK's international human rights obligations" in relation to freedom of religion.
The statements come a week after the government closed its consultation on registering and regulating supplementary religious schools, which the Department for Education says is necessary in order to protect vulnerable children.
Last week, Ofsted chief inspector Sir Michael Wilshaw told LBC radio he would use counter-extremism measures to intervene in "out of settings" religious schools where there was suspicion of extremist ideas being taught.
"We need to know if a Sunday school is being run, is it registered, is it being run properly by people that have been through proper safeguarding checks," he said, "and if that is done, then we are happy with that and we will only go in when we feel that there is a need to do so."
The statements resulted in calls for his resignation by MPs.
Howarth, a former Conservative defence minister, told The Telegraph: "He has flatly contradicted ministers who have assured us that there is no intention of investigating Sunday schools, and he has used as justification the very criticism that we have made that he wants to be even handed.
"Unless Sir Michael publicly renounces an intention to investigate Sunday schools, the minsters must sack him – he must go."