The UK has committed to a target of net zero emissions by 2050. However, speculation of an early general election in the weekend's papers was accompanied by speculation that fuel duty would be cut in an emergency budget next month.
At a time when "hottest year" records are now broken as a matter of routine, should the Prime Minister even contemplate cutting fuel duty?
Road transport is the largest emitting sector of the UK economy, accounting for more than a quarter of all UK greenhouse gas emissions. It is the only major sector where emissions are rising, largely due to the growth in demand for car and van travel.
Since 2011, fuel duty has been frozen. This means the price of fuel at the pump has been cut by 13% in real terms. The fuel duty escalator was first introduced in 1993 as an environmental tax, to stem the increase in pollution from road transport. If we are serious about tackling climate change and air pollution, why would we make such drastic reductions to environmental taxes?
The direct consequences of the freeze since 2011 have been: a 4% increase in road traffic; an additional 4.5 million tonnes of CO2; an additional 12 thousand tonnes of harmful NOx and 816 tonnes of PM10s; and up to 200 million fewer bus journeys and 60 million fewer rail journeys.
Government must do more to promote public transport. At the very least fuel duty should be linked to inflation in future budgets. The money raised from future increases in fuel duty should be ring fenced to accelerate the switch to electric vehicles and to encourage greater use of public transport.
Last week the Science and Technology Committee concluded that the Government's target for 'net-zero' by 2050 is undeliverable unless clean growth policies are introduced. It called for Government to promote public transport and reduce its cost relative to private transport.
Further speculation in yesterday's papers suggest that a cut in fuel duty is not yet a done deal. Apparently, Ministers have expressed concerns about the affordability. As well they might. The freeze in fuel duty since 2011 has cost the public purse more than £50 billion.
The Prime Minister has already set out his stall as emphatically pro public transport. In response to the terrible fires in the Amazon rain forest, he has also joined other world leaders in reiterating his commitment to the Paris agreement. It is time to put fine words into action.