Half a million more poor children will benefit from Government help targeted at deprived youngsters, Children's Minister Sarah Teather is expected to announce.

The pupil premium, currently worth £488 per youngster, is given to schools on top of their main funding. Headteachers are free to spend the extra money how they want.

However under existing arrangements, schools only receive the boost for pupils currently eligible for free school meals, which are available to children from low-income families.

The new system will widen its availability, meaning schools can claim for any child who has been registered for free school meals in the past six years.

Ms Teather said: "For too long social background has been a deciding factor in a child's achievement and future prospects.

"In a fair society, it's the Government's responsibility to close the gulf in achievement, where the poorest children are less likely to leave school with five good GCSEs than their less-deprived classmates.

"That's why I'm delighted we are today announcing the increase in the per pupil level of the pupil premium for 2012-13, as well as extending the eligibility to reach more children.

"It will help schools tackle the inequalities that have been a part of our state system for far too long. Thousands of children will finally be getting the extra support they need to succeed."

Ms Teather, who is due to make a written Commons statement later on Monday, will also tell Parliament how much each child's school will receive next year and what the overall pot will be worth.

Total pupil premium funding for 2011-12 is £625 million and is due to rise to £2.5 billion a year by 2014-15.