SCOTLAND must "step up to the plate" and do more to improve social mobility, a former Labour Cabinet Minister has insisted.

In a speech in Glasgow, Alan Milburn, chairman of the UK Government's Social Mobility and Child Poverty Commission, praised progress made on supporting children in the early years but said more was needed to ensure Scotland was a fair country.

He said there were 2.3 million children living in poverty in the UK. That represents nearly 20% and while Scotland has a lower rate of 17%, this, according to respected think-tank the Institute for Fiscal Studies, is set to rise to nearer 23% by 2020.

"These figures should shock and shame us all. Child poverty strangles progress. The more children there are in poverty the less social mobility there will be," declared Mr Milburn.

He pointed out that only one in 40 pupils from Scotland's most deprived households achieved three As in their Highers in 2011, compared with one in 10 across all income levels;

He said Scotland had the lowest levels of poor students in higher education institutions in the UK, with just in excess of 27% of students from working-class backgrounds in 2011/12. In 2004, 33% of the most senior civil servants in Scotland were privately educated, when fewer than 5% of Scottish children were educated privately.

Mr Milburn said: "The link between demography and destiny has remained stubbornly unbroken. If we are to make social progress that must change. It can only be done by enshrining as the twin objectives of education policy the raising of educational standards and the narrowing of educational inequalities.

"The one without the other will doom Scotland and Britain to lasting social division. Worse than that, a fast lane/slow lane education system can only deepen division. Raising the bar when it comes to schools standards is not enough if it doesn't also mean closing the attainment gap. Concerted action is needed."

The commission chairman noted that in Scotland the decision not to impose tuition fees had helped remove one barrier to higher education participation – fear of debt. But he went on: "The challenge now is to make the changes necessary to ensure that Scottish universities are open to the widest pool of talent.

"In 2010/11 just 2.7% of students at St Andrews were from Scotland's most deprived communities. There has been some progress ... Glasgow can be proud that it has the highest rate of participation from poorer areas across any of Scotland's most elite universities, but there is a very long way to go."

The Commission will publish its first report on social mobility in September.