General Motors has cast doubt over the long-term future of the Chevrolet Volt by claiming it may not be commercially viable and other rivals may overtake it with superior and more advanced technology.

GM submitted a regulatory filing report to the US Treasury yesterday and CEO Fritz Henderson claimed its “disclosures are consistent with our commitment to remain transparent and to keep the public informed of our progress”.

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The Volt is scheduled for a November 2010 launch, but the GM report claimed that the range-extender hybrid technology may not be fully developed in time to meet this target date. Pre-production Volt models began testing in June.

GM has marketed the Volt as the model to turn the company around, but the report claimed it “has not yet proven to be commercially viable”. GM is likely to sell each Volt at a large loss, although it would hope to recoup the development costs in future-generation models as Toyota has done with its Prius.

GM, which is majority-owned by the US Treasury, has based its entire business plan around securing US Department for Energy loans to help it develop advanced fuel technology vehicles. So far, despite three applications for a $5.7 billion (£3.4bn) share of the $25bn (£15bn) fund, GM has not been accepted and is due to make a fourth application this month.

“There can be no assurance that we will qualify for any remaining loans or receive any such loans even if we qualify,” said the GM report. It added that the US Treasury “is able to exercise significant influence and control over our business if it elects to do so”, but so far this has not been the case.

GM is also fearful that wealthier competitors will come up with similar technology to the Volt and it will be left behind.

“Our competitors and others are pursuing similar technologies and other competing technologies, in some cases with more money available,” said GM.

“There can be no assurance that they will not acquire similar or superior technologies sooner than we do.”

GM’s monthly sales have been declining since October 2007 and it will release its first financial results since exiting Chapter 11 bankruptcy protection at the end of September. It plans to start offering shares to the public from 10 July 2010, the one-year anniversary of its exit from bankruptcy protection.

No one from Chevrolet was immediately available for comment when contacted by Autocar.

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