LONDON - Tens of thousands more children in Britain are living below the poverty line, a report found on Monday, as MPs questioned Gordon Brown's commitment to eradicating child poverty.

The Joseph Rowntree Foundation said one in three children live in poverty and that little progress has been made in the past three years. It recommended increasing public sector pay.

Meanwhile the cross-party Treasury Commons Select Committee found that ministers had "drawn back from a wholehearted commitment" to halve child poverty by 2010.

In 1999, former Prime Minister Tony Blair promised to halve the number of poor children in a decade before completely eradicating the problem in 20 years.

Brown has taken up the cause, appointing Schools Secretary Ed Balls to head a unit designed to produce ideas to tackle child poverty.

The Rowntree foundation found that one in three children -- or 3.8 million youngsters -- actually live below the poverty line and urged a radical re-think on ways to tackle poverty.

The foundation, one of the country's largest housing and social policy research charities, said 200,000 more children were living below the poverty line.

"The question that must now be asked, for the first time since 1999 when the then prime minister (Blair) committed the government to ending child poverty in a generation, is whether that commitment is now much more than just rhetoric," it concluded.

"Overall poverty levels in 2005-06 were the same as they were in 2002-03. Child poverty in 2005-06 was still 500,000 higher than the target set for 2004-05."

Its researchers concluded that to tackle the problem, public sector pay had to be drastically increased.

The study found that schools, hospitals, local government and other public services were the biggest direct employers of low-paid workers aged 25 and over.

Half of all poor children live in working households.

The Treasury committee's Labour chairman, John McFall, a long-standing Brown ally, said the government's promise to halve child poverty by 2010 should not be seen as an optional extra. He added that the government's current spending plans "fail to provide a clear route map" to meet the targets.

The government said it had lifted thousands of children and more than a million pensioners out of poverty.