The European Commission is calling for extra public investment in the troubled Galileo satellite navigation programme.

Galileo will provide Europe with next-generation positioning and navigation services that are independent of either the US global positioning system (GPS) or planned Russian and Chinese rivals.

Transport commissioner Jacques Barrot is proposing member states put up a further £1.6bn (E2.4bn) to get the stalled 30-satellite scheme moving again.

Galileo already has E1.2bn of public funding. But only one test satellite has been launched since 2005. And a mixture of political and commercial issues have thrown the timetable into disarray.

The scheme is supposedly being delivered as a public private partnership (PPP). But the eight-strong consortium has still not created the new company to build and run the scheme. And there are on-going political problems around the location of both building operations and ground-based infrastructure.

Suppliers are also losing confidence in the market for Galileo's services and are questioning the original commitment to fund of two-thirds of the programme costs. The market for location devices is around £41bn (E60bn) at the moment, and could expand to as much as £274bn (E400bn) a year, according to the Commission. But the consortium is increasingly concerned that revenues may accrue to the suppliers of individual devices or services rather than the infrastructure provider.

One possibility is that Galileo will be deemed unworkable and will be scrapped altogether. But Barrot is convinced it should go ahead.

'Galileo will make a major contribution to Community policies, and embodies Europe's ambitions in space, technology and innovation,' he said this week.

It started in 2005 with the launch of an experimental satellite, but the completion date has slipped from 2008 to 2011 and it has already cost EU member states E388m (£264m) more than expected.