George Osborne will promise action now to ensure that the country does not "pay later" as he uses his Budget to deliver a grim warning about the global economy.
The Chancellor is expected to say that, although the UK's economy is "strong", the "storm clouds are gathering again".
Concerns about economic uncertainty will cast their shadow over Mr Osborne's eighth Budget, with the Chancellor planning to impose a further £4 billion of spending cuts to allow him to meet his fiscal target of getting the nation's finances into surplus by the next election.
He is expected to unveil "a Budget where we act now so we don't pay later" in order to meet the "new challenge" facing the country.
Mr Osborne briefed the Cabinet on his statement, telling ministers that it delivered on the Government's manifesto commitments while making sure the UK was well-prepared to deal "turbulent times" in the global economy.
The Prime Minister's official spokeswoman said his comments were met with the usual banging on the table - a traditional sign of approval.
David Cameron wrapped up the meeting, saying: "This is a pro-enterprise, pro-infrastructure, pro-devolution Budget that fully lives up to what this Government is all about - transformation."
Mr Osborne will make education reforms a key part of his plan to "put the next generation first", but his plan to turn all English schools into academies has been attacked by the unions and Labour.
Shadow chancellor John McDonnell has also accused Mr Osborne of choosing austerity as a way to further his own ambitions to lead the Tory Party.
The Chancellor is set to announce that every state school in England will become an academy by 2022 as he unveils a £1.5 billion package of additional funding for education in the Budget.
The cash will also allow some secondaries to offer a longer school day, remaining open after the traditional "home time bell" at 3.30pm for five hours or more a week of additional lessons or extracurricular activities.
But the National Union of Teachers accused the Chancellor of "undoing over 50 years of comprehensive public education at a stroke".
In a sign of the impact the economic "storm clouds" are having, the Financial Times reported that Mr Osborne will be forced to admit he has missed one target to cut Britain's debt as a share of GDP this year.
The Chancellor has blamed uncertainty over the prospects of China and the eurozone for dispelling the sunny mood of the Autumn Statement four months ago, when he said that higher-than-expected tax receipts would allow him to avoid cuts.
All eyes will be focused on whether Mr Osborne hikes fuel duty for the first time in five years - raising £1 billion for every 2p on a litre at the pumps - despite pressure from Conservative MPs to hold back. He has already given in to backbench protests by ditching a mooted plan to reform tax relief on pensions.
And there is speculation that he will nudge up insurance premium tax, while charity Scope said disabled people were "anxiously awaiting" the Budget statement amid concerns they may face further cuts to their benefits.
Already trailed ahead of the Budget is a £300 million package of investment in transport infrastructure in the North of England - including a green light for the HS3 plan to improve east-west rail links - as well as £80 million to take forward planning for the £27 billion Crossrail 2 north-south railway line through London.
Mr Osborne is also expected to confirm plans for a new £1.2 billion fund to release brownfield land for 30,000 new starter homes, as well as trials of driverless cars on British motorways, and he will confirm plans to crack down on the abuse of personal services companies by public sector workers seeking to minimise their tax bills.
Writing in the Independent, Mr McDonnell said: "There is no economic justification for the Chancellor's cuts. He has made a political choice to impose them. That has meant putting his own ambitions on the Tory leadership ahead of what is good for the country."
Mr McDonnell accused the Chancellor of planning to target the most vulnerable to plug the holes in his economic plans.
"This constitutes a new low. Labour will insist that he steps back from the brink," he said.