BT will be part-nationalised and every household will be offered free full-fibre broadband if Labour win the election, the party has said.
The announcement will be made today by leader Jeremy Corbyn, who plans to pay for the scheme by taxing multinational technology firms such as Amazon, Facebook and Google.
In a speech in Lancaster, Mr Corbyn will describe the new free public service – dubbed British Broadband – as “central to Labour’s plans to transform our country and economy”.
It will first be rolled out in communities with the poorest broadband access in the UK, such as rural areas, before being expanded across the country to all households and businesses by 2030.
There are more than 27 million households in the UK, according to the Office for National Statistics.
Mr Corbyn will say the “massive upgrade in UK’s internet infrastructure” will save the average person £30.30 a month, with funding also to come from the party’s Green Transformation Fund.
Ahead of his speech, Mr Corbyn tweeted: “Only 8-10% of premises in the UK are connected to full-fibre broadband.
“It’s 97% in Japan. Eight in 10 of us experienced internet problems in the last year. So we’ll make the very fastest full-fibre broadband free to everybody, in every home in our country. That’s real change.”
Labour put the cost at £20bn – a figure that was dismissed by people close to BT, who argued that it would be double that sum.
Sky News’ political correspondent Jon Craig said it was a “big moment” and a “huge and controversial pledge”, adding that it was “going further than Labour have done before on renationalisation”.
He said there would be “strong reaction” to the announcement, which has already been attacked by the Conservatives as a “fantasy plan” that would cost taxpayers tens of billions of pounds.
Digital, Culture, Media and Sport Secretary Nicky Morgan, who is standing down at the election, said: “Corbyn is clearly so desperate to distract from his party’s divisions on Brexit and immigration that he will promise anything, regardless of the cost to taxpayers and whether it can actually be delivered. What reckless idea will be next?”
Shadow chancellor John McDonnell insisted the plan was feasible, saying it had been fully costed.
He said: “This is public ownership for the future. A plan that will challenge rip-off ‘out-of-contract’ pricing – and that will literally eliminate bills for millions of people across the UK.
“Every part of this plan has been legally vetted, checked with experts, and costed.”
Sky News’ technology correspondent Rowland Manthorpe said the policy would likely prove popular with voters, but suggested other broadband providers could feel “hugely threatened”.
He said: “Every poll and focus group I’ve seen would suggest this policy is going to be extremely popular. Not just the free broadband but the tech company tax – people are really angry about that issue.
“Buying BT is the easy bit. The hard part will be working out how this affects all the other firms, which could be hugely threatened by a state provider.”
Labour had already said it wants to nationalise gas, electricity and the railways – the latter of which has the backing of the majority of the public, according to a Sky poll.
Julian David, chief executive of techUK, and a member of the government’s digital economy council said the plans would be a “disaster” for the telecoms industry, adding that it would shift costs of investment being borne by the private sector onto the taxpayer.
He added: “Renationalisation would immediately halt the investment being driven not just by BT but the growing number of new and innovative companies that compete with BT. Full Fibre and 5G are the underpinning technologies of our future digital economy and society.
“These proposals would be a huge set back for the UK’s digital economy which is a huge driver for growth.”
Philip Jansen, BT chief executive, told the BBC: “These are very, very ambitious ideas and the Conservative Party have their own ambitious idea for full fibre for everyone by 2025 and how we do it is not straight forward.
“It needs funding, it is very big numbers, so we are talking £30-40bn and if you are giving it away over an eight year time frame it is a another £30-40bn. You are not short of £100bn.”
Prime Minister Boris Johnson is also talking about infrastructure out on the campaign trail, promising investment that he says will keep the high street open for business.
Under his plan, pubs, shops, cinemas and music venues will all qualify for cuts in business rates, and the Tories say they will also reverse some of the rail cuts of the 1960s.
Places which will be candidates for a £500m fund include Ashington, Seaton Delaval and Blyth in Northumberland and Skelmersdale, Thornton-Cleveleys and Fleetwood in Lancashire.
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The bicycling prime minister also wants to extend the cycling infrastructure he introduced in the capital when he was mayor of London to the rest of the country.
Mr Johnson said: “For too long, too many towns and villages across Britain have been overlooked and left behind. We will invest in these communities and help people put the heart back into the places they call home.
“We will be able to save our high streets, keep pubs and post offices open and reconnect places to the rail network half a century after they were cut off.”
And in an eye-catching campaign commitment of their own, the Liberal Democrats have said an extra £100bn will be pumped into combating climate change if the party gets into power.
Party finance spokesman and former cabinet minister Sir Ed Davey will use a speech in Leeds on Friday to make the announcement and will also launch an attack on the financial plans of both Labour and the Tories.
“The Conservatives have made our economy weak – much weaker than people realise,” he will say.
“Too many people can’t live a secure, happy and fulfilling life. And too many businesses face crippling uncertainty over their future. Yet so far, the economy debate in this election has been a debate between fantasies.
“Fantasies born of nostalgia for a British Imperial past. Competing with fantasies from a failed 1970s ideology.”
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