Scotland's flagship 2030 target for reducing greenhouse gas emissions is now out of reach, the government's independent advisers have warned.
The Climate Change Committee (CCC) said the measures that would be needed to achieve the target by the end of the decade were "beyond what is credible".
It accused ministers on "failing" on ambitious goals and urged them to focus instead on hitting the target "at the earliest possible date".
Chris Stark, chief executive of the Climate Change Committee, told the BBC that ministers had just not done the job of putting the policies in place.
He said: "This is the first time, anywhere in the UK, that we've said there's a target that can't be met.
"It's a shame we have to give that message to the Scottish government but what's behind it is a lack of progress all round."
Scotland's emissions reduction target for 2030 is tougher than for the UK as a whole.
The Scottish Parliament legislated to cut greenhouse gases by 75% compared with the UK's target of 68% by the same date.
However the committee's assessment said the Scottish Government's actions "continue to fall far short" of what is legally required to reach the targets.
It adds that most key indicators of delivery progress are off track, significantly so across a number of areas.
These include electric van sales, tree-planting and recycling rates.
Heat pump installations were at half the recommended level in 2023, with just 6,000 fitted.
That will need to increase by a factor of 13 - to 80,000 annually - by the end of the decade.
Net Zero Secretary Mairi McAllan responded: "The Climate Change Committee have always been clear that meeting the legislated 2030 target – agreed by Parliament on a cross party basis - will be extremely challenging, and may not be feasible.
"We remain fully committed to meeting our target of net zero emissions by 2045."