The Liberal Democrats have pledged to reward people who improve the energy efficiency of their homes with a 10-year council tax discount under pre-manifesto plans.

Households could save at least £100 a year by permanently cutting their energy bills in a bid to help with the cost of living while simultaneously meeting Britain's climate change targets.

Energy Secretary Ed Davey said his was the only party offering both lower energy and council tax bills, adding: "A 10-year council tax cut will make action to end your home's energy waste a no-brainer.

"And to meet our legal climate change obligations, the cheapest way is to make rapid progress in cutting our emissions by saving the energy we now waste.

"We cannot build a stronger economy without creating a greener, more sustainable economy too."