The government's approach to tackling child poverty has lost momentum and is in "urgent need" of a major rethink, a charity has said.
More than 3.8m children still live below the poverty line
A Joseph Rowntree Foundation (JRF) report said there has been no sustained progress in the past three years. One in three UK children live in poverty.
A report by the Treasury select committee fears the pledge to halve child poverty by 2010 is in doubt.
Ministers say progress has been made, but acknowledge more needs to be done.
The JRF report is also concerned that the number of children in working families that need to escape poverty is rising.
Back in 1999 the-then Prime Minister, Tony Blair, promised to halve the number of poor children in 10 years and to eradicate child poverty in 20 years.
He also set a more short-term goal to reduce the number of children living in poverty to 3.1 million by April 2005.
Although the total has fallen by 600,000 since then, the government is still 500,000 short of reaching its original target.
The report's authors say the most serious setback was an increase of 200,000 children living in poverty in 2005/6 - taking the total to 3.8 million, or one in three children, if housing costs are taken into account.
The JRF report acknowledges that tax credits have made a positive difference to many families.
But it points out that half of all children in poverty are in working families, suggesting more needs to be done to tackle the problem of low wages.
"Progress on child poverty has stalled at a level that is only half way to the target set of two years ago," said the report's co-author Peter Kenway.
"Tax credits may be working, but they are not enough on their own.
"Yet the government's budgetary and legislative programme set out this autumn contains no substantial new ideas about what should be done," he added.
'More to be done'
The Child Poverty Action Group agrees that "more radical policies" are necessary.
"The culture of inequality in Britain has a high cost to individual lives and the whole nation," added the charity's chief executive, Kate Green.
"We cannot afford not to address the educational failure, health costs and social division that poverty brings to our communities."
Meanwhile, the Treasury select committee report says the government's commitment to halve child poverty by 2010 appears to be in doubt.
It says this is because the government has failed to explain what it is doing to meet the target.
WHO IS POOR?
Household income less than 60% of median household income after housing costs
Single person no children - net income less than £108 pw
Couple with two children - net income less than £301pw
Lone parent with one child - net income less than £223pw
It warned any backtracking would represent a "conscious decision to leave hundreds of thousands of children in poverty for longer than is necessary or desirable".
The committee said the government's Comprehensive Spending Review - which sets out the long term budgeting - did not explain how the 2010 mark would be met.
Caroline Flint, minister for employment and welfare reform, defended the government's anti-poverty strategy, which she said had already lifted 600,000 children and more than a million pensioners out of poverty.
"As the JRF has recognised, a tremendous amount of progress has been made in improving the lives of people over the last 10 years," she said.
"But we know that more needs to be done and we firmly believe that sustainable work is the best way out of poverty."
The Department for Work and Pensions has already announced a new cross-government Child Poverty Unit, which it hopes will ensure better co-ordination of efforts by government and other agencies.