Paris - The world's top-selling carmaker Toyota has come joint last in a Greenpeace ranking of carbon emission efforts by car companies, according to a list published on Thursday during the COP26 climate summit.
The campaign group gave Toyota and US-European firm Stellantis "F minus minus" grades for decarbonisation efforts including phasing out engines that burn planet-warming fossil fuels in favour of electric vehicles.
Minimising carbon emissions in the supply chain and reusing or developing greener technology for car batteries were among the factors examined in the report that compared 10 major carmakers.
General Motors received the least damning rating with a C- grade, followed by a D for Volkswagen and D- for Renault.
All the other firms, including Ford, Honda and Hyundai-Kia, were rated F plus or minus.
"Toyota, the world's number-one car seller last year, is the most stubborn in holding onto internal combustion engines," said Ada Kong, senior project manager of the auto industry campaign at Greenpeace East Asia.
The Japanese giant is also "most vocal in such advocacy, domestically and abroad", Kong said in a statement.
Toyota said in September it would invest $13.2 billion (R200bn) in batteries for electric and hybrid cars by 2030. The carmaker also recently unveiled its first mass-market electric car, the bZ4X, which is one of 15 fully electric vehicles that are in the pipeline between now and 2025.
Toyota declined to comment ahead of the publication of the emissions report, in which Greenpeace urged carmakers to embrace fully-electric vehicles.
"Some Japanese companies, such as Toyota, are confident that hybrid technology is an effective alternative to the internal combustion engine," the report said.
"However, the real-world emissions reduction and fuel economy of hybrid vehicles are not as good as expected," it said, noting that plug-in hybrids only reduce emissions by an estimated one-third, compared with petrol or diesel cars.
The assessment came as world leaders met in Glasgow this week as part of the COP26 climate conference - billed as vital for the continued viability of the 2015 Paris Agreement, which set a goal of limiting global warming to 1.5 degrees Celsius.
Greenpeace said none of the 10 automotive firms had announced plans to phase out combustion engines before 2035, which would make the 1.5-degree goal "almost impossible".