The last government saddled this country with the deepest recession since the 1930s, the biggest deficit of any developed country, and a welfare system that was out of control. Now Labour have pledged to vote against our plans to make sure it never happens again.

Since coming to power, we have taken the tough decisions necessary to get our public finances back under control. And we are making progress: in just the last two years we have cut the deficit by 25%. But more still needs to be done. And with welfare costing £200 billion per year - more than the NHS, education and defence budgets combined - the benefits system must take its share of the burden.

In Labour's last year in power, every working family faced a bill of £3,000 just to pay for working-age benefits. And though it is difficult to believe, when we came to power, some families were receiving more than £100,000 per year just in housing benefit.

It cannot be fair that a family going out to work every day, often on low wages, has to pay more tax to support people receiving much more than them in benefits. That's why we have already capped benefits to ensure no household can receive more in welfare payments than families earn going out to work. Likewise, in recent years, out-of-work benefits have increased at almost twice the rate of earnings. During times of austerity this isn't fair, and it cannot continue.

These decisions haven't been easy, but they are right. And so is the decision to withdraw paying child benefit to the richest 15% of the country. During times of economic difficulty, when we are taking tough action to keep welfare spending under control, how can we justify spending nearly £2 billion per year on child benefit to the wealthiest people in society?

From Monday, families with a taxpayer earning more than £50,000 will have some of their child benefit removed. 85% of all families with children are entirely unaffected and will continue to receive child benefit in full; 90% will benefit in full or in part.

We have always been clear that those with the broadest shoulders should carry the greatest burden when it comes to balancing the nation's books. Those liable for the removal of child benefit fall in the top 15% of earners and nearly half of the households affected by this change have a household income of more than £100,000.

These policies haven't always been popular - but they are fair and reasonable, and will save £7 billion per year by 2017-18. Labour opposed capping benefits at £26,000 per year and they opposed withdrawing child benefit from the richest in society - now they oppose capping increases in benefits too.

But it is no longer good enough for Labour to simply oppose every tough decision we take to clean up the mess they left behind. If they really support increasing benefits by more than earnings, if they really want to continue spending £2 billion a year on child benefit for the rich, and if they really are happy with families receiving over £100,000 per year in welfare, it is time we heard them say it - and how they would pay for it.

Until Labour commit to increasing taxes on the average working household by £470 per year, own up to yet more borrowing, or name which public services they think aren't worth keeping, they will always be the party of an unsustainable, unfair and out-of-control welfare state.