The biggest players in the automotive industry are refusing to back a commitment to sell only zero-emissions cars and vans by 2040, dealing a blow to hopes for major progress on the climate crisis at COP26.

The UN climate summit in Glasgow, chaired by the United Kingdom, wanted governments, manufacturers, and investors to promise to “work towards all sales of new cars and vans being zero emission globally by 2040, and by no later than 2035 in leading markets,” according to a draft declaration seen by CNN Business ahead of Wednesday’s scheduled release.

The non-binding pledge was promoted by the summit’s organizers as central to efforts to keep carbon emissions in line with the 2015 Paris Agreement, which seeks to cap the rise in global temperatures to 1.5 Celsius above pre-industrial levels.

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But Toyota and Volkswagen, the world’s biggest carmakers by vehicle sales, BMW, Nissan and other manufacturers all declined to sign the declaration.

Climate activists said China and the United States, the world’s biggest car markets, were refusing to sign up to the pledge. Germany, home to Europe’s biggest car industry, was also not ready to back it, according to a German government source.

“What’s gravely concerning today is that major economies like the US, Germany, China, Japan and manufacturers like VW, Toyota and Hyundai could not even bring themselves to sign a declaration on electric vehicles that promises less than what’s actually required to maintain climate security,” Martin Kaiser, executive director of Greenpeace Germany, said in a statement on Wednesday.

CNN Business has contacted all three governments for comment.

Toyota said in a statement that there wasn’t enough time to put such a wide-ranging policy in place by 2040, particularly in parts of Asia, Africa, and the Middle East, which lack “the environment to promote electrification.”

“Because of this, we found it difficult to commit to a joint declaration and did not participate in the signing of it at this time,” the Japanese company said in a statement.

Volkswagen, which has invested heavily in electric cars and plans to build six “gigafactories” in Europe by 2030, said it was fully committed to that strategy “as the primary means to achieve zero emission vehicles.”

But, like Toyota, it said the 2040 deadline didn’t account for the differences in pace at which zero-emission vehicles would be adopted around the world. It also said that any accelerated shift to electric vehicles had to be “in line with an energy transition towards 100% renewables.”

“While transformative speed is of the essence, the pace of transformation will still differ from region to region … depending, among others on local political decisions driving EV [electric vehicles] and infrastructure investments,” it said in a statement.

BMW also refused to sign the pledge because of what it called “considerable uncertainty” about how a complete global shift to zero-emission vehicles would be supported, especially across significantly different markets.

The company said it had zero emission technology “ready today” and that models of its Rolls Royce and Mini brands built from the early 2030s onwards would be battery electric vehicles only.

Stuck in the slow lane?

Some carmakers, however, are ready to back the COP initiative.

Ford has signed the pledge and said it expected up to 40% of its global vehicle output “to be fully electric by 2030.” Mercedes-Benz owner Daimler said it would sign the COP26 declaration, but added that its own objectives were “even more ambitious.”

It said it was preparing for Mercedes to go all electric “by the end of the decade, where market conditions allow.”

“In total, investments into battery electric vehicles between 2022 and 2030 will amount to over €40 billion ($46 billion),” it said in a statement.

Volvo, based in Sweden, is also expected to sign, having already announced its intention to only sell fully electric cars by 2030.

Benjamin Stephan, energy and transport campaigner at Greenpeace Germany, told CNN Business it was “not at all surprising” that the country’s main carmakers didn’t sign up to the COP26 pledge, singling out BMW as being reluctant to take a full electric path with its lines, in contrast to Volkswagen’s declared electric car strategy.

But he also criticized the pledge to only sell zero-emission vehicles by 2040 as a “step in the right direction, but way too slow” in order to meet the 1.5 Celsius and net zero targets by 2050.

— CNN’s Amy Cassidy, Mayumi Maruyama, Anna Cooban and Chris Liakos contributed to this story.

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