Christians do not have a right to wear a cross or crucifix openly at work, the British Government is to argue in a landmark court case.

In a highly significant move, ministers will fight a case at the European Court of Human Rights in which two British women will seek to establish their right to display the cross.

It is the first time that the Government has been forced to state whether it backs the right of Christians to wear the symbol at work.

A document seen by The Sunday Telegraph discloses that ministers will argue that because it is not a "requirement" of the Christian faith, employers can ban the wearing of the cross and sack workers who insist on doing so.

The Government's position received an angry response last week from prominent figures including Lord Carey, the former Archbishop of Canterbury. He accused ministers and the courts of "dictating" to Christians and said it was another example of Christianity becoming sidelined in official life.

The Government's refusal to say that Christians have a right to display the symbol of their faith at work emerged after its plans to legalise same-sex marriages were attacked by the leaders of the Roman Catholic Church in Britain.

Today, a poll commissioned by The Sunday Telegraph shows that the country is split on the issue. Overall, 45 per cent voters support moves to allow gay marriage, with 36 per cent against, while 19 per cent say they do not know. However, the Prime Minister is out of step with his own party. Exactly half of Conservative voters oppose same-sex marriage in principle and only 35 per cent back it.

There is no public appetite to change the law urgently, with more than three quarters of people polled saying it was wrong to fast-track the plan before 2015 and only 14 per cent said it was right to do so.

The Strasbourg case hinges on whether human rights laws protect the right to wear a cross or crucifix at work under Article 9 of the European Convention on Human Rights.

It states: "Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief, and freedom, either alone or in community with others and in public or private, to manifest his religion or belief, in worship, teaching, practice and observance."

The Christian women bringing the case, Nadia Eweida and Shirley Chaplin, claim that they were discriminated against when their employers barred them from wearing the symbols. They want the European Court to rule that this breached their human right to manifest their religion.

The Government's official response states that wearing the cross is not a "requirement of the faith" and therefore does not fall under the remit of Article 9.

Lawyers for the two women claim that the Government is setting the bar too high and that "manifesting" religion includes doing things that are not a "requirement of the faith" and therefore are protected by human rights They say that Christians are given less protection than members of other religions who have been granted special status for garments or symbols such as the Sikh turban and kara bracelet, or the Muslim hijab.