Mr Brown said that the child tax credit, which comes into force in April, should increase support for families dramatically.

April's new tax credits are the biggest financial boost for mothers since the introduction of child benefit, Gordon Brown, Chancellor of the Exchequer

According to the Treasury, 90% of families will be eligible for the credit, with the money paid directly to the mother rather than to fathers.

An ICM poll commissioned by the Treasury suggests that paying the tax credit to mothers rather than fathers enjoys 70% public support.

New credit

The credit will mean that most mothers receive �26.50 a week for the first child, made up of child benefit of �16.05 and a further �10.45 additional credit.

The credit is available to families with earnings of up to �58,000.

Children currently receive support through the working families tax credit, the disabled person's tax credit, and income support or jobseeker's allowance, as well as the existing children's tax credit.

From April the child tax credit will integrate all this support into one package.

It will be paid in addition to child benefit, which remains a universal benefit - paid to all families with children.

In addition, families with earnings of up to �66,000 will get some help if they have a child less aged less than 12 months.

Complexity

However, there are concerns that people may be put off claiming the tax credits, as they are complicated.

There is evidence that existing tax credits are under-claimed, and critics suspect this is because of their complexity.

People who think they may be eligible for the new tax credits can contact the Inland Revenue either online, through its telephone helpline, or through an Inland Revenue enquiry centre