Business Secretary Vince Cable has said there is a "compelling case" to speed up the extension of the controversial HS2 high speed rail link to the cities of the north.
His intervention came as HS2 chairman Sir David Higgins prepared to outline his plan for an accelerated construction timetable while reducing the cost of the £50 billion infrastructure project.
Sir David, who will publish his report on Monday, will also issue an appeal to the main political parties to unite behind the scheme.
In an interview for The Observer, Mr Cable - a Lib Dem - made clear his support for the scheme, arguing that bringing forward the northern link could help rebalance the British economy.
"Creating jobs outside London, and closing the gap between north and south, has been one of this Government's top priorities," he said.
"On every visit I make to the north of England, I've heard businesses and council leaders make a compelling case for getting to the north more quickly by accelerating parts of the HS2 build.
"That would ensure the economic benefits can be shared sooner by everyone around the country and deserves serious consideration by government."
In contrast, shadow chancellor Ed Balls said last week that it was important that Sir David could show that costs "have come down markedly".
At present the cost of HS2 is put at £42.6 billion, with a further £7.5 billion needed for the high-speed trains.
Fiercely championed by some but bitterly opposed by others, the scheme's first phase will see a new line run from London through Tory heartlands to Birmingham and is scheduled to be completed in 2026.
The second phase, taking the line in a Y-shape to north west and north east England is set for completion around 2032/33.
Launching his report in Manchester, Sir David will say that he would like work to start on the second phase at the same time as the first phase.
He is also expected to recommend a completely new station at Euston - the site for the line's London terminus.
Sir David, the former London Olympics supremo who has joined HS2 Ltd after being Network Rail chief executive, is also expected to recommend scrapping plans to link HS2 with HS1, the London to Kent coast Channel Tunnel high-speed line.
HS2 is facing a number of obstacles over and above the strong opposition by residents who face years of disruption while the building work goes on.
Mr Balls is not the only Labour politician to express reservations about the scheme. Former chancellor Alistair Darling and former industry secretary Lord Mandelson have also questioned the project's viability.
In addition, the current Transport Secretary Patrick McLoughlin has said that the legislation for phase one of the project will not get through Parliament before next year's general election.