The simmering row over religious relations in Britain was threatening to boil over last night after controversial interventions by politicians from both main parties.

The Government's race Minister demanded the sacking of a Muslim teaching assistant who refuses to remove her veil at work, accusing her of "denying the right of children to a full education".

Phil Woolas said Aishah Azmi's stand meant she could not "do her job", and insisted barring men from working with her would amount to "sexual discrimination".

Meanwhile, shadow Home Secretary David Davis launched a stinging attack on Muslim leaders for risking "voluntary apartheid" in Britain, and expecting special protection from criticism.

In an article for the Sunday Telegraph, Mr Davis warned of "closed societies" being created in the UK, and said religious divides threatened to "corrode" fundamental values such as freedom of speech.

The outspoken comments came at the end of a week in which the furore over race relations has grown steadily, after Jack Straw admitted he asked female Muslim constituents to lift their veils during private discussions.

Some Muslim groups have condemned the Leader of the Commons for "selectively discriminating" on the basis of religion.

But Mr Davis - in an apparent hardening of the Conservatives' attitude to radical Islam - expressed sympathy with Mr Straw's position, and suggested the problem went deeper, affecting the "very unity of our nation".

He wrote: "What Jack touched on was the fundamental issue of whether, in Britain, we are developing a divided society.

"Whether we are creating a series of closed societies within our open society. Whether we are inadvertently encouraging a kind of voluntary apartheid."

Mr Davis added: "Are we going to allow the splintering of loyalties, the division of communities, that will corrode the foundations of our society?"

The increasing polarisation of the argument over integration has been illustrated by two high-profile cases.

Headfield Church of England junior school in Dewsbury, West Yorkshire, confirmed on Friday that it had suspended 24-year-old Ms Azmi, who has taken her case to an employment tribunal.

The school is understood to have deemed face-to-face contact was essential in her role as a bilingual support worker. It has stressed that the action had "nothing to do" with religion.

Ms Azmi insisted yesterday that she had been willing to remove the garment in class as long as there were no adult males present.

But Mr Woolas said: "She should be sacked. She has put herself in a position where she can't do her job. She cannot teach a classroom of children wearing a veil."

Labour's Lord Ahmed, the first Muslim peer, delivered a broadside against politicians and the media for "demonising" the community.

He said: "Let's be honest, there are people in our community who call themselves Muslims who have been threatening our national security. It is very unfortunate.

"But the problem is that the politicians and some people in the media have used this for demonisation of entire communities, which has become a very fashionable thing today."

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