"Incandescent light bulbs waste 95% of the energy they use as heat.
Phasing these out and replacing them with efficient alternatives can
help reduce emissions and energy bills.
"We are pleased that UK retailers and energy suppliers are voluntarily phasing out these lamps before European rules are introduced later this year."
Lord Hunt claimed the bulbs contained a smaller amount of the substance than mercury thermometers, which the EU has banned, but the government was looking at safer alternatives such as LED lights, which did not contain any mercury and had a longer life.
The move to low-energy light bulbs is described as "one of the most positive moves the government has made recently".
Palace of Westminster claims to have saved 61% of its energy costs by swapping to low energy bulbs.
