Tax cuts linked to the carbon tax worth will be abandoned  in next week's federal budget, due to a drop in the projected carbon price.

Climate Change Minister Greg Combet confirmed on Wednesday  that the Gillard government would ''defer'' its plan to increase the tax-free  threshold in 2015.

Mr Combet said the shelved tax cut would have been ''in the  order'' of $1.59 per week for most people earning up to $80,000 a year.

As part of its assistance to households when the carbon tax  was introduced, the federal government tripled the tax-free threshold to $18,200  in 2012. This was due to rise to $19,400 in 2015.