The Northern Council of Mosques, representing 400 mosques, says this "encroaches" on religious freedom.
The Muslim supplementary schools would have to comply with plans for tighter scrutiny over "out-of-school education settings" if the plans were introduced.
The government's consultation on the proposals closes on Monday.
And the Department for Education has indicated that it makes "no apology" for wanting to ensure children are properly protected.
David Cameron has warned that "teaching intolerance" had to be stopped.
But in a response, the mosque leaders say the plans are based on "the flawed assumption that radicalisation takes place within some madrassas" and that such "control and monitoring" over lessons would "effectively lead to a form of state sanctioned religious expression". [BBC] Read more
