The drive over the past decade to tackle child poverty is leaving the poorest families behind, according to a powerful cross-party report.

The MPs welcomed progress since 1997 and hailed the recognition across parties and between Westminster and devolved government over the scale of the problem.

But the Scottish Affairs Committee fears that the efforts so far have been most helpful to those just below the poverty line and are in danger of leaving the worst-off further behind.

A major factor in their report is the sheer complexity of the benefits and taxation systems, with tax credits in particular seen as being so complicated that claimants are deterred.

Stories of poor families being asked to pay back tax credit money which was wrongly calculated had added to this deterrent effect.

As well as helping families with children, the report stressed the need to help young adults, describing them as the parents of tomorrow. By doing this, the MPs argued, there was a chance to break the cycle of poverty.

Among the measures they highlight to achieve this is equal treatment of young adults in terms of benefits and the minimum wage.

They also advocate making child benefit the same for each child in a family, rather than giving more for the first child, arguing that there is a strong correlation between larger families and poverty.

Committee chairman Mohammad Sarwar, Labour MP for Glasgow Central, said: "The cycle of deprivation must be broken if we want to reduce child poverty.

"While we are pleased that some progress has been made in the past 10 years, much more must be done. There are 250,000 children still living in poverty in Scotland today so action is urgently needed."

Mr Sarwar said committee members looked forward to the government's response to their recommendations, adding: "We also look forward to continuing the historically close collaboration between the UK Government and the Scottish Executive in order to tackle child poverty and build on the work already done."

The government had set targets in 1997 of halving child poverty by 2010 and eliminating it altogether by 2020 but the report claimed "significantly more resources" would be needed to reach the 2010 target.

While MPs said the introduction of child tax credits had been a "key factor" in reducing child poverty, they also highlighted serious concerns about the take-up levels for these compared to child benefit, which is available to all parents.

The report said: "Given the complexity of the tax credit system, we are concerned that the government should do its utmost to ensure families are aware of their entitlements."

The report indicates support for the simplicity of universal benefits such as child benefits, even although these go to the better-off.

However, issues such as the general level of income tax or the provision of free school meals were outwith its remit.

Livingston MP Jim Devine spoke of constituents holding down jobs in a hairdresser or filling station who were still unable to put food on the table, saying it was scandalous that anyone in employment remained in poverty.

John Dickie, the head of the Child Poverty Action Group in Scotland, welcomed the call for more resources to help the poorest families. He claimed research showed that £4bn a year needed to be spent if the 2010 target was to be reached and added: "That might sound a lot but it is only 0.3% of GDP. Surely it's the least our children deserve."

Douglas Hamilton, of Save the Children, said: "The number of children living in poverty in Scotland is unacceptable. Today's report adds further pressure on government to do more to end child poverty."