CHILDREN's charities have accused the Government of moving the goalposts to mask the fact that its welfare cuts are throwing thousands more children into poverty.

Agencies have criticised a speech by the Work and Pensions Secretary, Iain Duncan Smith, in which he said that it was a waste of money to give benefits to parents who were suffering from a drug or alcohol addiction.

He called for a new "multi-dimensional" measure to calculate levels of child poverty, moving away from its current definition of those living in homes on less than 60 per cent of the median income. The latest figures for median income in the UK put it at £419 a week -down £13 from the previous year.

Speaking in London at the Kids Company charity, on Thursday of last week, Mr Duncan Smith said: "For a poor family where the parents are suffering from addiction, giving them an extra pound in benefits might officially move them over the poverty line. But increased income from welfare transfers will not address the reason they find themselves in difficulty. . .

"Worse still, if it does little more than feed the parents' addiction, it may leave the family more dependent, not less, resulting in poor social outcomes and still deeper entrenchment. What such a family needs is that we treat the cause of their hardship - the drug addiction itself."

But the chief executive of the Children's Society, Matthew Reed, accused Mr Duncan Smith of peddling a "fiction" on poverty.

"Millions of children up and down this country are living in poverty because their families do not have enough money to live on, access to decent housing, or affordable childcare. Let's separate fact from fiction. The vast majority of families in poverty are struggling because they can't afford the basics - not because they are wasting cash on drink and drugs."

The Head of Policy and Campaigns at Family Action, Rhian Beynon, said: "We already have a child-poverty measure; changing the goalposts will not benefit those families in and out of work struggling to keep their heads above water."

The Government admitted earlier this month that the latest one-per-cent cap on benefits from April, announced by the Chancellor, George Osborne, in the Autumn Statement, would push 200,000 children into poverty. And figures released this week in a parliamentary written answer show that in half of these families, one parent is already working.

In cities such as Leicester and Nottingham, where child poverty rates are 32 and 35 per cent respectively - compared with a national average of 22 per cent - campaigners have warned that they are on the verge of "a child-poverty emergency".

The Bishop of Bedford, the Rt Revd Richard Atkinson, said that people in his diocese were warning of a "tsunami of poverty". "A nation's greatness is measured by how it treats its weakest members."

New research published this week by the think tank the Resolution Foundation found that the poorest households are likely to be hit again with a rise in council tax in April.

The Foundation surveyed councils, and found that although some planned to make savings from other budgets, 74 per cent said that either households that did not previously pay any council tax would have to start paying some of the bill, or discounts to low-income working households would have to be reduced.

The Archbishop of Canterbury, the Most Revd Justin Welby, has called on the Church to step in and fill the void left by the declining welfare state. The Church, he said, should "grasp the opportunity" offered by its expanding social role in running food banks and other social-action projects, as well as educating one million children.

The Christian charity Housing Justice has launched a new website, www.tellmystory.org.uk, to offer a platform for people affected by the cuts to respond to the Government's rhetoric of "welfare scroungers". The charity said: "The myth . . . needs to be challenged."