In the week that the Government committed up to £500 billion to rescue Britain's banks, the man charged with campaigning for ministers to spend £3.5 billion on halving child poverty is feeling remarkably bullish.

Martin Narey, chief executive of Barnardo's and chairman of the Campaign to End Child Poverty coalition, knows that any squeeze on the Budget next spring could jeopardise the Government fulfilling its promise to halve child poverty by 2010. That is why he was among the estimated 10,000 people who attended the campaign's Keep the Promise rally in Trafalgar Square last Saturday.

“I think you have to accept that it worked,” Mr Narey said, “because on the day that he was going off to France to meet European leaders about the credit crunch, the Prime Minister found 45 minutes in his diary to see me and other members of the End Child Poverty board to discuss the issues. I felt that, in the most difficult circumstances, we hoisted child poverty back up the political agenda.”

Mr Narey welcomed Mr Brown's announcement at the Labour Party conference last month of a legal duty on government to eradicate child poverty in Britain by 2020, but he is anxious to ensure that the promise of being “in this for the long haul” is not abandoned. He said: “Politically, it would be their greatest achievement; it would be Gordon Brown's legacy. To be able to go to the country and say, ‘We have halved the child poverty we inherited when you first elected us.' It would be an astonishing claim to be able to make.”

A passion to tackle inequality is what brought Mr Narey to Barnardo's in 2005 after almost 30 years in the public sector, including seven as director-general of the Prison Service.

With an income of £200 million, the charity runs about 400 services for more than 100,000 disadvantaged children, young people and their families. Mr Narey has overseen significant growth at the charity and he is confident that the organisation can weather the economic storm. He admitted, however, that the slump in house sales would slow the flow of legacy income and he worried about voluntary sector pension schemes.

“Unless the market recovers dramatically, the next time our pension scheme is evaluated it will be in significant deficit,” he said. “It will be interesting to see whether the pensions regulator takes a rather longer-term view about that. I think he will have to.”

The proportion of donors giving to children's charities in Britain has fallen from about 12 per cent to 7 per cent in the past 15 years. “I have to accept that if you ask most people on the street to name a children's charity in the UK, they'll say the NSPCC. Fifty years ago they would have said Barnardo's. We need to address that.”

The charity will be launching its first big television advertising campaign next month, with prime-time slots on ITV, Channel 4, Channel 5 and digital TV. It will highlight the needs of children in trouble, such as the 782 young people aged 12 to 14 who were give short-term custodial sentences last year.

Mr Narey believes that custody can work in the right circumstances, but he is convinced that locking up young people for a few weeks and then merely returning them to where they come from “is just so futile it beggars belief”.

He knows that the cost of the advertising - “much more than £1 million but much less than £2 million” - is more than the charity has spent before. However, he argued: “If it gets people to think about the way we deal with young people, and, of course, get them to think about the fact that Barnardo's might be an organisation that wants to offer some solutions on this, then it will be worthwhile.”

The lowdown

Who Martin Narey, chairman of the Campaign to End Child Poverty and chief executive of Barnardo's, the children's charity, since 2005. Former posts include youngest director-general of the Prison Service, chief executive of the National Offender Management Service and a Permanent Secretary at the Home Office

What The Campaign to End Child Poverty is a coalition of 120 children's charities, child welfare organisations, faith groups, trade unions and others set up in 2002. 600,000 children in the UK have been lifted out of poverty since 1999 but 3.9 million children - one in three - remain there. This increased by 100,000 last year

When The coalition wants child poverty to be halved by 2010 and eradicated by 2020

Why “will fail to keep its promise if it does not commit £3 billion in tax credits and benefits in the next Budget”

— Hilary Fisher, director for the Campaign to End Child Poverty

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