A climate change expert has backed calls from the Scottish Green party for Scottish ministers to commit to cutting carbon emissions to zero by 2040.
The Scottish Government's proposed target for the forthcoming Climate Change Bill is a 90 per cent reduction by 2050, an increase on the 80 per cent target currently in force.
However, Glasgow Caledonian University researcher Dr Keith Baker, co-founder of the Scottish Carbon Accounting Group, confirmed Green analysis indicating the new target would allow a slowdown from the current rate of emissions reduction.
He said: "Scotland has earned a reputation as a world leader on reducing carbon emissions but we're in danger of throwing that lead away.
"If we look at the trend over recent years we can see that if we maintain the current rate of emissions reduction we can hit net-zero by 2040, so a target of 90 per cent by 2050 clearly represents a slowing down in ambition.
"There are huge advantages to reducing fuel poverty and inequality, and creating lasting jobs for the future, if we keep up the momentum.
"The forthcoming Climate Change Bill is an exciting opportunity for Scotland to play its part in meeting the global climate agreements made in Paris. I urge Scottish ministers to, at the very least, not slow down the rate of action."
Scottish Greens' climate change spokesman Mark Ruskell said: "There's a growing consensus that we need to use the forthcoming Climate Change Bill to set an ambitious zero-emissions target, and it's welcome to have expert backing for our call to maintain the current trajectory and aim for 2040.
"We cannot afford to slow down if we're serious about meeting our responsibilities.
"The Government has talked up the phasing out of petrol and diesel vehicles but we need to see other measures in the Climate Change Bill such an acceleration of the green bus fund and a nitrogen budget for farming to help drive the changes needed to reduce emissions from transport and agriculture."
Mr Ruskell said the Government should also look at further carbon-cutting measures such as setting a target which keeps fossil fuels in the ground and using the budget to speed up investment in low-carbon infrastructure.
A Scottish Government spokeswoman said: "Scotland is a world leader in tackling climate change emissions, thanks to the actions of this government.
"We support the Paris Agreement aspiration for global emissions to reach net zero levels in the second half of the century, and are taking time to fully consider all responses to the public consultation on our bill proposals.
"Very few other countries have any emission reduction targets in legislation, much less a statutory target for each and every year.
"Unlike the UK Government, we have proposed new legislation to set more ambitious long term targets in direct response to the Paris Agreement."
The public consultation on the new climate change bill closed on September 22.