Shadow chancellor George Osborne said a Tory government would deliver speeds of 100 megabits per second (Mbps) to the "majority" of homes by 2017.

He said cabling in rural areas could be paid for by private investors or part of the licence fee.

Mr Osborne told the BBC's Andrew Marr Show: "In the 19th Century we built the railways, in the 20th Century we built the motorways, in the 21st Century let's build the super-fast broadband network that will create hundreds of thousands of jobs for Britain."

The Tories said money from private investors would pay for better cabling.

But the Conservative Party said it might not be attractive for private companies to install broadband cabling in some rural areas, in which case a proportion of the BBC licence fee could be used.

It said the BBC could continue to set aside 3.5% of its licence fee - which currently goes to the digital switchover - to fund broadband expansion.

For Labour, Treasury Minister Stephen Timms said: "On broadband it's not Britain but the Tories that are playing catch-up.

"Labour have already announced measures for rolling out broadband across the country - and the Tories have opposed the plans to make that happen. "

That presents all kinds of questions of course, not least of which is 'O rly?', but would we even need that sort of capacity realistically - maybe multiple HD streams and mass cloud computing, say?

Their proposals will never work.

The thing is, if people are provided with something, they will generally find a use for it. Also, if BBC iPlayer HD didn't exist, it would be a heck of a lot harder to convince many home customers they need to upgrade their connection speed.

just how much you can do with 100Mb

...just how much you can do with 100Mb

3D porn with pizo-electric motor feedback

It'll never happen.

Ever.

Their proposals will never work.