Child Poverty Action Group has published a special edition of the journal Poverty in which experts on child welfare and poverty ask "Where next for Gordon Brown? His first hundred days".

The contributors urge the new Prime Minister to place tackling child poverty and redressing inequalities in the UK at the forefront of the Government's agenda.

Kate Green, Chief Executive of Child Poverty Action Group, said: "It is shocking that as Brown takes office 3.8 million children are still living in poverty in the UK.

"The new Prime Minister must use his first hundred days to set out how the Government will deliver the resources needed to halve child poverty by 2010. He will be judged by voters on his ability to meet the Government's historic promise to end child poverty."

Hilary Fisher, Director of End Child Poverty, said: "Brown's first days in office provide the opportunity to introduce fresh policies and inject new thinking, and to show he really is the children's anti-poverty champion."

Gordon Brown became the new British Prime Minister Wednesday, bringing an end to Tony Blair's decade in power.

Brown, who has waited 10 years for his turn as Prime Minister, met the Queen on Wednesday afternoon at Buckingham Palace , where she formally offered him the role of Prime Minister.

On taking up his new office, Brown promised a fresh start after a decade marred largely by the Iraq war and growing voter distrust.

"This will be a new government with new priorities," Brown said in a statement to reporters outside the Prime Minister's residence at 10 Downing Street, reports Reuters.

"I've heard the need for change ... and this need for change cannot be met by the old politics," he said. "And now let the work of change begin."