US greenhouse gas emissions barely decreased in 2024, leaving the world's largest economy off track to achieve its climate goals, according to an analysis released Thursday, as the incoming Trump administration looks set to double down on fossil fuels.

The preliminary estimate by the Rhodium Group, an independent research organization, found a net fall of just 0.2 percent in economy-wide emissions.

Lower manufacturing output drove the modest decline, but it was undercut by increased air and road travel and higher electricity demand.

Overall, emissions remain below pre-pandemic levels and about 20 percent below 2005 levels, the benchmark year for US commitments under the Paris Agreement.

The accord aims to limit global warming to 1.5 degrees Celsius above pre-industrial levels, to avert the worst catastrophes of planet-wide heating.

But with 2024 effectively static, decarbonisation must accelerate across all sectors.

"To meet its Paris Agreement target of a 50-52 percent reduction in emissions by 2030, the US must sustain an ambitious 7.6 percent annual drop in emissions from 2025 to 2030," the report said - an unprecedented pace outside of a recession.

Trump has signaled plans to roll back President Joe Biden's green policies, including rules that require sweeping cuts from fossil fuel power plants and provisions of the Inflation Reduction Act, which channels hundreds of billions of dollars into clean energy.

Should these plans materialize, the US would likely achieve only a 24-40 percent emissions reduction by 2035, the report concluded.

Even under Biden, the US has logged more tepid reductions compared to some other major emitters.

German greenhouse gas emissions fell by three percent in 2024, following a 10 percent year-on-year drop the previous year, according to Agora Energiewende.

The European Union's emissions are forecast to have dropped by 3.8 percent in 2024, according to Carbon Brief, a UK-based analysis site. (AFP)