George Osborne, the Shadow Chancellor, insisted yesterday that there was no disagreement between himself and David Cameron over using the tax system to support marriage and said he was pushing ahead with a tax break for married couples as a key part of the Conservatives’ election strategy.

The Tory leader has been categorical that a government run by him would reward people for marrying and that those in civil partnerships would benefit as well as heterosexual couples. He cites research showing that almost half of cohabiting couples split up before their child’s fifth birthday, compared with one in twelve married couples.

But insiders have said that Mr Osborne was concerned that the Tories would alienate voters if they appeared to stigmatise unmarried mothers and cohabiting couples.The Shadow Chancellor said that there was no disagreement on the issue, although he conceded that there were differences on other areas of policy.

In an interview with The Daily Telegraph Mr Osborne said: “Marriage will be recognised in the tax system. If I am David’s Chancellor, which I fully expect to be, then I will implement that. “There is no disagreement there at all. Of course, everyone is entitled to choose how to live their lives and some marriages do fail, but we know that, in general, marriage is an institution that contributes to building a stronger society. That is why Labour was wrong to stop supporting it through the tax system.”

Mr Osborne said that although he and Mr Cameron did not always agree, “on the big fundamentals — the changes necessary to the Conservative Party, keeping the Conservative Party on the centre ground in British politics and the economic changes that we need to make — we pretty much see eye to eye.”

The Shadow Chancellor said that his focus was on how the Conservatives would run the country, but he insisted that the party was not complacent. “I don’t underestimate the ability of the Labour Party to win, even under Gordon Brown. I don’t think he’s a particularly attractive Prime Minister. But I don’t assume that they’ve lost it.”

Times Recommends

• Catalogue of failings ‘leaves others at risk’
• Tourists told to stay away amid Venice floods
• Google generation has no need for rote learning