Treasury has revealed it made an error in modelling over projected changes in child poverty.
The error affects projections of how many children are expected to be in low-income households and the number of children expected to be lifted out of poverty by 2020/21.
The errors affect the assessment of the Government's Families Package announced in December 2017 and comparisons with the National Government's Family Incomes Package announced in May 2017.
"The error likely led to an overstatement of the projected impact both packages would have on the reduction of child poverty," Secretary of the Treasury, Gabriel Makhlouf said in a statement.
The error does not affect the number of people set to be helped by the Government's Families Package or the amount of extra income they will receive, Mr Makhlouf says.
"The extent of any change in the projections on child poverty is still being determined," Mr Makhlouf says.
"Because the error applies equally to comparisons with the previous Government's Family Incomes Package, the estimated relative impact of the two packages is essentially unchanged."
Treasury is aiming to have revised projections available in the second half of February.
An external review will be put in place over the error.