Geoff Hoon said he was 'delighted' to be handed the transport brief
Ministers are to consider new high-speed rail lines - a year after the idea was rejected as too costly.
Transport Secretary Geoff Hoon said he would not rule out any option - even levitating Maglev trains.
He also wants more electrification of existing lines and more hard shoulders on motorways opened up to cars.
The Tories, who have pledged to build a high-speed rail line and scrap Heathrow's third runway plan, said the "non-announcement" was "empty words".
In a statement to MPs, Mr Hoon, who took over the transport brief earlier this month, said: "In order to stimulate Britain's economic growth and support our position as a leading world economy it is essential that we make the right long-term investments in our transport infrastructure and that we plan for future growth, in a way which is consistent with reducing greenhouse gas emissions overall."
I am passionate about developing practical plans for further electrification on key routes and about the assessing the scope for new lines, including high speed ones
A new National Networks Strategy Group, chaired by transport minister Lord Adonis, will bring together senior officials from the Highways Agency, Network Rail, the Treasury and other government departments to examine the options.
Mr Hoon said he wanted to "accelerate" the work his department was doing on both long and short-term planning for the future of road transport, with more hard shoulder-running to increase capacity, and rail.
In his first appearance before the Commons transport committee, he said: "I am passionate about developing practical plans for further electrification on key routes and about assessing the scope for new lines, including high-speed ones.
"I believe both options have the potential to bring real benefits for rail passengers."
Asked if he would rule out the development of ultra-high-speed Maglev lines, he said: "The track costs are something like three times as much for a Maglev line as for a conventional line.
"We are certainly not closed to it but we have to be realistic about what we can afford."
He also rejected suggestions the current financial turmoil threatened large-scale transport projects which relied upon investment from banks.
Department for Transport permanent secretary Robert Devereux said it was "possible" that some projects, such as current work on the M25, would be delayed.
But Mr Hoon said: "There is no reason why we should not move ahead more quickly with a number of these projects, not least because they do not depend on large amounts of private finance."
He also rejected criticisms about overcrowding and poor service on Britain's inter-city and commuter lines, saying many of country's railways were now the "envy" of other European countries.
He said overcrowding on the West Coast Mainline was a sign of its success, but added that more carriages would be added to trains.
Mr Hoon, who uses Midland Mainline trains to travel to his Nottinghamshire constituency, said he was "delighted" to have been made transport secretary, as his father was a railwayman.
His predecessor Ruth Kelly was criticised by MPs for ducking the issue of high-speed rail and electrification of the existing network when she unveiled a five-year plan for the railways last year.
Both options were rejected as too expensive, although Network Rail is carrying out a feasibility study on high-speed rail which is due to be published next year.
The Lib Dems accused Mr Hoon of "fobbing" rail passengers off with more "short-termism and tinkering".
"We now need assurances that this programme will result in the major investment in our railway infrastructure that is so desperately needed," said transport spokesman Norman Baker.
"Years of bad policy has created a 'cattle-truck Britain and the wrong approach now will make it a permanent reality."
The Conservatives are proposing to create a new £15bn line linking London St Pancras, Birmingham, Manchester and Leeds - saying it would cut 63,200 Heathrow flights a year.
Shadow transport secretary Theresa Villiers outlined the plan at last month's party conference.
She said on Wednesday: "This is just the latest example of 11 years of spin and reannouncements from Labour. It is a deeply unimpressive statement from the new transport secretary.
"If Geoff Hoon really wants to improve our national transport networks, he should back our plan for a high speed rail link. That would make a real difference to jobs, the economy and to rail overcrowding."