All couples who enter into a lifelong commitment should be able to call their relationship marriage, Culture Secretary and Minister for Equalities, Maria Miller, has told MPs.

This afternoon, the House of Commons is debating the Marriage (Same Sex Couples) Bill ahead of a vote on Tuesday evening.

The Conservative MP, who recorded a video of support for the Out4Marriage campaign in September, began her speech by saying: “Parliament should value people equally in the law, and enabling same-sex couples to marry removes the current differentiation and distinction.

“There is no single view on equal marriage from religious organisations. Some are deeply opposed, others tell us that they see this as an opportunity to take their faith to a wider community.

“I know that some colleagues in this House feel they cannot agree with this bill for principled religious reasons.

“That is a stance I entirely respect.

“I don’t think it’s the role of government to tell people what to believe. But I do think that parliament and the state have a responsibility to treat people fairly.”

Mrs Miller continued: “Some say this bill re-defines marriage. But, marriage is in fact an institution with a long history of adaptation and change.

“In the 19th Century, Catholics, Baptists, atheists and many others were only allowed to marry if they did so in an Anglican Church, and in the 20th Century changes were made to recognise married men and married women as equal before the law.

“Suggestions that this bill changes something that has remained unchanged for centuries, simply does not recognise the road marriage has travelled as an institution.”

Mrs Miller insisted religious freedom would be protected and that no faith organisations would be forced to marry gay couples.

She dismissed concerns from Tory opponents that the European Court of Human Rights could order British churches to marry gay couples.

“It is simply inconceivable that the court would require a faith group to conduct same-sex marriages in breach of its own doctrines” – not my words but the words of the eminent QCs, Lord Pannick, Baroness Kennedy and Lord Lester,” said Mrs Miller.

Labour’s Shadow Home Secretary Yvette Cooper welcomed Mrs Miller statement.

She said: “Parliament has the chance today to support loving couples who want to get married.”