Network Rail is to roll out "high speed mobile broadband" across the country's busiest lines, Transport Secretary Patrick McLoughlin has announced.
The plans will be industry funded, and if successful will make it feasible for passengers to watch streamed videos on their mobiles.
70% of passengers should have access to the faster internet by 2019, according to the Department for Transport.
The move was announced at the Conservative party conference in Manchester.
A BT spokeswoman said the company was "disturbed" by an MPs' report that claimed the government's rural broadband scheme was mismanaged and left the internet provider with a near monopoly.
We are disturbed by today's report, which we believe is simply wrong and fails to take on board a point-by-point correction we sent to the committee several weeks ago.
We have been transparent from the start and willing to invest when others have not.
It is therefore mystifying that we are being criticised for accepting onerous terms in exchange for public subsidy - terms which drove others away.
The taxpayer is undoubtedly getting value for money.
BT faces a payback period of around 15 years on its rural broadband investments in spite of the subsidies available.
The DCMS (Department for Culture, Media and Sport) has imposed a rigorous auditing process that ensures every penny is accounted for.
The government's £1.2bn rural superfast broadband scheme has been mismanaged and has left sole provider BT in a "quasi monopolistic position", the chairwoman of the Commons spending watchdog has said.
Margaret Hodge, Public Accounts Committee Chair, said: "Overall, BT is supposed to provide at least 90% coverage in rural areas but it is preventing local authorities from publishing proper information on the areas the company will and will not cover.
"Details of speed and coverage in each local project are also being kept confidential, preventing other suppliers from developing schemes aimed at reaching the remaining 10% of premises and stopping communities and others from identifying alternative ways of providing superfast broadband."
Britain faces dramatic variations in broadband speed within cities, according to a new report, with Birmingham home to the biggest gap between fast and slow.
A study by uSwitch.com found that many consumers are also left in the slow lane in London, Bristol, Northampton and Glasgow.
The difference between fastest and slowest broadband speeds in Birmingham is 89%, while London’s slowest postcode district is EC2Y, which covers Barbican.
Telecoms regulator Ofcom said its auction of 4G airwaves raised £2.3 billion, well below the government’s £3.5 billion target.
The Chancellor George Osborne had mentioned the projected income as part of his claim in the Autumn Statement that borrowing could be reduced.
ITV News Consumer Editor Chris Choi reports:
The Chancellor will be disappointed with the amount raised by the auction, but it is good news that we can now get on with implementing 4G.
Consumers will benefit from the good number of competitors in the 4G market, and we must now encourage investment to get the necessary infrastructure put in place nationally.
The results of the 4G auction are a game changer for the mobile industry and consumers alike.
The combination of spectrum just sold off should bring faster speeds, greater consistency and improved coverage.
While George Osborne won't be too impressed with the amount raised by the auction, it has clearly been expensive for some providers. What is important is that this extra expense isn't passed onto customers - especially in the form of tariff price rises.
While some providers claim not to be imposing a premium for 4G, it's vital that prices remain affordable for those unwilling - or unable - to make the big switch."
Labour said the government raising £2.3 billion in the 4G auction instead of the £3.5 billion that was budgeted was a "blow" to George Osborne's economic plan.
This is yet another blow to George Osborne’s failing economic plan.
It shows how foolish and short-termist the Chancellor was to bank this cash in the autumn statement to make his borrowing figures look less bad.
He couldn’t bring himself to admit that borrowing was up so far this year but his trickery has now badly backfired.
Today's announcement will deliver a significant economic boost to the UK. Spectrum use is worth more than £50 billion to the UK economy and 4G mobile broadband is a key part of our digital growth strategy so, I am delighted the auction has been completed.
We worked hard through the autumn to make sure that the operators would be able to use this spectrum 6 months earlier than expected. The benefits will been seen in the UK from the summer onwards as mobile operators deliver competitive high speed mobile broadband services.