"We're pleased the label clearly demonstrates the Nissan LEAF to be a best-in-class option, reflecting that it's a pure electric vehicle, uses no gas, has no tailpipe and has zero emissions, " said Scott Becker, senior vice president, Finance and Administration, Nissan Americas.

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It also has yet to offer any voluntary emissions goals, and currently generates zero percent of its energy from renewable sources.

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Toyota has always believed that fuel cell technology is the long-term answer for zero emissions driving, so the company pulling back from a tepid market should not be viewed as a surprise.

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But currently fewer than one in 200 British homes would qualify as zero-carbon, so in order to bring major reductions in domestic greenhouse gas emissions, the government has to tackle existing homes too.

BBC: ANALYSIS