The “$100 laptop”, designed to close the world’s digital divide by making low-cost computers available to children in poor countries, will actually sell for $188.

News of the price hike comes amid fears that the non-profit One Laptop per Child (OLPC) project risks floundering amid fierce commercial competition and wavering support from governments in developing countries.

An estimated 5 billion of the world's 6.3 billion people do not have access to a computer, a gap that OLPC aims to close by starting production next month of its cheap, pared-down PC.

However, the group has now been forced to nearly double the $100 price originally targeted by Nicholas Negroponte, its founder. News of the latest hike comes amid concerns that OLPC is struggling to book firm orders.

Simon Tates, of Forrester, the researcher, wrote in a recent note: "There is ... the risk that any one of the component vendors or manufacturing partners could turn sour on the project if delays and rising costs start to affect the project’s long-term viability."

OLPC, which had previously set the price of its XO laptop at $176, blamed the weak dollar and rising costs of commodities including nickel and silicon for the latest rise.

The XO laptop uses a microprocessor from Advanced Micro Devices (AMD) and a Linux software system developed by Red Hat – choices that have left some of the biggest names in the computing industry out in the cold.

Work is also being carried out on a prototype low-cost microscope that could be used with the XO machine to provide diagnosis of HIV/AIDs, TB, and malaria, which kill more than six million people every year.

But the project has sparked several rounds of fractious debate since its launch two years ago, encountering opposition from rival technology companies, aid workers and African politicians.

For example, while Microsoft, the world’s largest software group, is now testing the laptop to determine whether it is capable of running its dominant Windows operating system, Bill Gates, the Microsoft co-founder and the world’s biggest philanthropist, has already advised buyers to "get a decent computer", rather than opt for an OLPC machine.

Soon after the project was announced, Craig Barrett, the chairman of Intel, the main rival to AMD in the processor market, said: "Mr Negroponte has called it a $100 laptop - I think a more realistic title should be the $100 gadget.

"The problem is that gadgets have not been successful ... it turns out what people are looking for is something that has the full functionality of a PC. We work in the area of low-cost, affordable PCs, but full-function PCs, not handheld devices and not gadgets."

OLPC has given as good as it has got: earlier this year, Mr Negroponte criticised Intel for launching its own low-cost PC, the Classmate, which he claimed was deliberately designed to underprice and undermine his project.

"Intel should be ashamed of itself," he told CBS News. "It's just - it's shameless."

But news of the Classmate’s impending launch is understood to have led several key countries – including Brazil, Pakistan and Thailand – to waiver in their commitment to the OLPC project.

Meanwhile, both Microsoft and Intel have stepped up their own efforts to bring computers to the estimated 80 per cent of the world's population who currently do not have access to PCs. Both Intel's World Ahead Program and Microsoft's Unlimited Potential scheme are focused on packaging current hardware and software in ways that are appealing to poor governments .

Mr Yates said: "The motivation behind all these efforts is a complex mix of business opportunity, self-preservation, and corporate citizenship ... a healthy balance of all three is the key to success in the long run.

"Efforts that focus too much on self-preservation — essentially delivering a solution into the market to block a potential competitor — will ultimately fail as too reactive. If a company focuses just on being a good citizen, financial stakeholders both inside and outside the organization could derail the effort at the first sign of trouble.

"And, if it’s just about the business opportunity, a company could be waiting for a long time before the investment pays off."

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