The Works and Pensions Secretary has demanded that the government introduce a tax break for married couples.
Iain Duncan Smith wants George Osborne to make changes by next year’s budget to show the government was serious about promoting marriage.
The idea of giving a tax break for married couples was a key Tory manifesto pledges which if not carried out would let the public dismiss as tokenism, Mr Smith has said to have warned David Cameron.
It is being feared that the pledge which the prime minister said would be honoured by 2015 was going to fall by the wayside unless implemented soon.
But the problem lies within the coalition with the Lib Dem leader Nick Clegg opposing it by accusing the Tories that it was trying to create the 1950 model of suit wearing, bread winning dad and apron clad home making mother.
Mr Cameron championed the idea of a marriage tax break when in opposition, although the proposal was watered down to the point where it would be worth only about £150 a year to most.
He said encouraging marriage would help in avoiding divorce proceedings as it would encourage more couples to stay together and produce greater stability for children.
The move was bitterly opposed by the Lib Dems, who argue it was wrong to favour marriage over cohabitation. The Coalition agreement allows them to abstain on any vote on the issue, and gives priority to their tax plan of raising the income tax threshold to £10,000.
Mr Duncan Smith received an unstinted support from the Bishop of Chester. Peter Forster said recognition of marriage in the tax system was one way of sending a ‘powerful symbolic message from government into society, and stress the importance of marriage in the society.
He argued that good marriages were not just a benefit for the couple themselves, and their children, but serve to strengthen the wider society of which they are a part.
A strong respect for marriage would actually support single parents, and others who have the care of children.
Speaking in a House of Lords debate on child development, the bishop urged ministers to act without delay, adding that there would be some changes needed to be carried out to implement the issue before the next budget it would become an unfulfilled pledge of the government as the next election would approach.
Former Tory Lord Chancellor Lord Mackay of Clashfern also urged the Chancellor to act swiftly in the interests of children.
Ministers have not specified exactly how the pledge to recognise marriage in the tax system by 2015 will be implemented.