Health Secretary, Jeremy Hunt, spoke out on Sunday in support of the upcoming equal marriage bill, saying that “religious freedom is not just for heterosexuals”.

Mr Hunt said that nobody should be denied the right to marry in a church, and that people should be allowed to enter into the “sacred” bond of marriage based on their own beliefs.

On Tuesday, the House of Commons will vote on the Marriage (Same Sex Couples) Bill, which would make it legal for same-sex couples to marry.

Mr Hunt, a supporter of the reforms, said on Sunday: “Every year thousands of people choose to marry in a church rather than a register office because they believe marriage is sacred.

“Religious freedom is not just for heterosexuals – we should not deny anyone the right to make a lifelong commitment to another person in front of God if that is what they believe and that is what their church allows.”

This came as twenty current and former constituency chairmen warned Mr Cameron that legalising equal marriage could harm Tory election prospects. 

Yesterday, Foreign Secretary William Hague said the Conservative Party would look out of touch if they failed to support marriage equality.

Education Secretary, Michael Gove, also offered his support to the proposed legislation and re-iterated that teachers would not be disciplined for refusing to “promote” it.

On Monday, in an article in the Times newspaper, Culture Secretary Maria Miller said being gay was not a good reason to prevent couples marrying.

Recognising the split in the Conservative Party over the issue, Mrs Miller conceded: “As a party we have grappled with many decisions that have not been plain sailing and we have not always found easy accord, whether that is within Westminster or within our current coalition.”

She also said the bill would be safe from challenge via the European Court of Human Rights.

It will receive its second reading tomorrow by an overwhelming majority, thanks to support from Labour and Liberal Democrat MPs.

However, Downing Street is anxious that Mr Cameron and Tory supporters of equal marriage are not outnumbered by opponents.

Up to 130 of the party’s 303 MPs are expected to support the bill, with a similar number having indicated their opposition.