New green taxes will hit the poorest hardest, according to a new report.

The study, from the Joseph Rowntree Foundation, found that the use of energy, water, petrol and diesel is disproportionately higher in lower income households, meaning that flat rate taxes are "regressive".

The effect can be substantially reduced through the state benefit system, the report argues, although there would still be winners and losers among the poorest households due to varying levels of fuel and water use.