Tesla boss Elon Musk has attempted to quell speculation about the future of his fledgling electric sports car company, by speaking frankly to reporters about its situation.

The PR offensive follows an announcement earlier this week revealing that the price of Tesla's Roadster and Model S would have to go up to help keep the company viable.

"An audit... found that the true cost [of the Roadster] was closer to $140k," said Musk. "Which was obviously an extremely alarming discovery and ultimately led to a near complete change in the make-up of the senior management team.”

Tesla is currently fulfilling orders for customers who have paid $90,000 or $98,000 for the car. As a result, equipment that was intended to be included in the price of the Roadster - including the bespoke overnight 70A charger - has become optional to help bridge the price gap. Each charger will cost $3000.

“This has been incredibly hard for me personally,” Musk told reporters. “It’s like eating glass.”

The PayPal founder - whose fortune is estimated at $350 million - made clear that he couldn't "shoulder the weight of the company alone", and admitted that the last round of finance for the firm had been difficult to obtain.

Musk insisted that Tesla had a strong future, however, and that the new Model S electric saloon would be on the market by 2011. The firm also plans to double its production rate for the Roadster in the spring - from 15 to 30 cars per week - helping to create economies of scale.

Defiant Musk was keen to make much of Tesla's deal with Daimler, where it will supply electric drivetrains for the Smart. The new EV Smart will sell for around $20,000 in the States, it was revealed. "It's an endorsement of Tesla's engineering," he said.

The Tesla boss was frank in his assessment of the situation. "I think people are taking a little bit of a risk on Tesla," he concluded. "But it's worth it. It's the hottest car in the world."

Will Powell