The Government's adviser on social mobility has called on politicians from all parties to work together and combat child poverty after new estimates warned the UK will be home to 3.5 million poor children in 2020.
Alan Milburn said: "Willing the ends without the means today merely becomes a broken promise tomorrow. Across the political spectrum, party leaders now need to come clean about what they plan to do to hit the targets, or what progress they can deliver if they expect to fall short."
A report by the Social Mobility and Child Poverty Commission concluded there were positives in the Government's strategy in tackling child poverty, including the extension of childcare support for low-income families and a greater acknowledgement of the problem of working poverty than before.
However, it criticised a lack of any clear measures to assess progress and the absence of a detailed plan covering what needs to happen to jobs, wages and benefits to ensure poverty goes down.
Britain's plan to end child poverty is "doomed" to fail with the UK set to be home to 3.5 million poor children by 2020, the government's adviser on social mobility warned.
The Government's draft strategy for the next three years on tackling child poverty was a "missed opportunity" and fell short of what is needed to stop the numbers rising, a report by the Social Mobility and Child Poverty Commission, chaired by former health secretary Alan Milburn said.
It was a "farce" and "particularly lamentable" that ministers had been unable to agree on how to measure poverty after rubbishing existing measures, Mr Milburn added.
The former Labour MP said: "The Government's approach falls far short of what is needed to reduce, yet alone end child poverty in our country.
"Our new research shows that the gap between the objective of making child poverty history and the reality is becoming ever wider."
The Prime Minister's social mobility tsar has criticised the Government's child poverty strategy saying it "sidestepped" the fact that the situation has been "stagnating".
Alan Milburn, the chairman of the Government's Social Mobility and Child Poverty Commission, said independent projections expect child poverty to rise significantly by the end of the decade.
Writing in a blog on the commission's website, Mr Milburn called the new document "a list, not a strategy" that failed to engage with expectations that the 2020 target to eradicate child poverty "will be missed by a country mile".
He was joined in his condemnation by Labour MP Frank Field, who stressed the strategy "has learnt nothing from the mistakes of the past."
Mr Field said, "The bickering between the Chancellor and the Work and Pensions Secretary distracts from the crunch issue in tackling child poverty - what stops the poorest children from being up there with children from richer families when they begin their first day at school?"
The estimated five million workers surviving on less than the living wage are "the forgotten people of Britain" who "desperately need a new deal", said the Labour MP behind a damning social mobility report.
Alan Milburn said the Government needed to do more for low-paid workers who "stand on their own two feet, do the right thing, go out to work, strive not shirk".
A nine-to-five job is no longer enough to help low-paid families out of poverty, the Government's social mobility tsar will warn.
Former Labour minister Alan Milburn will highlight how stagnating incomes and rising prices are preventing families from supporting themselves.
In its first report, the government's Social Mobility and Child Poverty Commission is also expected to warn that middle-class children face lower living standards than their parents for the first time in more than a century.
Mr Milburn is expected to recommend using some of the funding set aside for helping poor children to boost the chances of the middle class.
Meanwhile, Nick Clegg warned against taxing pensioners more in order to tackle the problem.
The Government's social mobility adviser Alan Milburn has said that around 83% of the jobs created in the next decade will be professional jobs. He argues the UK must capitalise on this growth to extend access to all parts of society.
In today's report, he writes: "There is every chance that, like the 1950s, the next decade can be a golden era when it comes to opening up opportunities in our society.
"But that will not just happen. It has to be made. With a genuine national effort we can break the corrosive correlation between demography and destiny that so poisons British society."
The Government's independent adviser on social mobility has said that the senior ranks of top professions remains a "closed shop". He said that data on the social diversity of top professions showed what amounted to "social engineering on a grand scale".
54% of top journalists were privately educated and a third at Oxbridge
13 private schools taught 10% of all MPs
35% of MPs are privately-educated after 2010 election
12 private schools taught 43% of all members of the House of Lords