The number of people living below the poverty line in the UK is set to increase over the coming years, according to a report from the Institute for Fiscal Studies (IFS).

The Child and Working-Age Poverty from 2010 to 2020 study says that 2.2 million children and two million working-age adults were living in conditions of absolute poverty in 2009-10. The IFS expects these figures to increase significantly, predicting that 600,000 more children and 800,000 more adults will be below the poverty line by 2012-13.

Poverty in the UK is defined in terms of income; people with a household income at least 60% below the national average are living in conditions of poverty. In 2009, the poverty line for a single adult stood at £165 per week (after tax and national insurance payments), the IFS said.

The government hopes to reduce poverty levels through the introduction of a new single monthly benefit payment - called the Universal Credit - in 2013. The IFS admitted that the Universal Credit should directly reduce the number of children in poverty by 450,000 by 2020-21. Poverty among adults should also be significantly reduced by the policy.

However, the IFS added that the Universal Credit could ultimately fail to prevent an increase in poverty levels, because it will be "more than offset" by other planned reforms, such as the alteration of the index of inflation used for means-tested benefits.