Plans to introduce a city-wide municipal wireless internet network in San Francisco have hit a major hurdle, with supporters of the scheme now wondering whether it makes financial sense.

Under the original proposals, residents of the Californian city were benefit from access to the internet wherever they wished for as little as £10 a month.

However, according to the sector-tracking website MuniWireless.com, questions have been raised as to whether such networks would generate sufficient revenue to justify the multi-million pound investment required to build and maintain them.

"Cities and companies are rethinking the models that they are adopting," said Esme Vos, the website's founder.

"It's all about economics and risk-sharing now."

While such schemes have been taken up or attempted in numerous cities in the US, at present few places in the UK have public-access wireless networks, meaning that users have to rely on home broadband connections.

Since commercial Wi-Fi hot spots were introduced in the UK in 2002, the focus has been largely on single access points, though London's Canary Wharf district boasts blanket coverage as does Norwich.

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