Growth forecasts have been downgraded, the Chancellor said.
It was 2.4% for 2016, but has now been revised down to 2% by the OBR, George Osborne said.
It is predicted to be 2.2% in 2017 rather than 2.4% and 2.1% in each of the three years after that.
Mr Osborne said Britain was expected to "grow faster than any other advanced economy in the world".
Chancellor George Osborne said Britain is well-placed to cope with global "headwinds" as long as we "act now so we don't pay later".
He said the Office for Budget Responsibility has revised down growth in the world economy and in world trade.
Deputy Political Editor Chris Shop says George Osborne's gloomy global economic outlook is also a warning against a vote to leave the EU.
Britain is on course for a budget surplus by the end of this parliament, George Osborne has said as delivers his Budget.
He said the deficit was down by two-thirds and that the economy was stronger "because we confronted our country's problems and took the difficult decisions".
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Plans to take every school in England out of the control of local councils and extend the school day are set to be announced in the Budget.Read the full story ›
Tim Farron has urged George Osborne to "abandon his unnecessary surplus target" to avoid more "pain" for the public.
The Liberal Democrat leader said the surplus was not needed to balance the books and abandoning it would allow "vital services" to be funded.
Mr Farron said: "George Osborne made a choice to commit himself to a spending surplus. The results of that choice are now clear - he is missing his own targets but it's the public that will pay for his decision with more years of pain and cuts.
"What George Osborne forgets is that his decisions aren't just some political theatre - every choice, every cut hurts ordinary people.
"Having missed two of his three self-imposed targets, he should do the right thing and abandon his unnecessary surplus target."
New funding will be made available for prosthetic running blades for amputee children, the Chancellor is due to announce in the Budget.
Writing in the Telegraph, Sarah Hope, whose daughter Pollyanna lost her right leg below the knee in a collision with a bus, said £1.5 million would be made available.
Ms Hope launched a campaign in protest at the NHS policy of only providing walking prosthetic legs, despite claims the Government wanted to build a 2012 Paralympics legacy.
She said the Chancellor agreed to fund the limbs after she contacted him directly
She said: "Some of the cash – £500,000 – will buy running prosthetic limbs to let 500 children run, jump and swim, while the NHS will undertake a review of its provision of prosthetic limbs this summer."
Ahead of the 2016 Budget, ITV News spoke to people who may be directly affected by changes made in the Chancellor's eighth statement.Read the full story ›
Shadow Chancellor John McDonnell has criticised George Osborne's plans for education reform ahead of the Budget.
Radical plans to transform every school in England into academies and abolish the traditional 3.30pm finish time are set to be unveiled.
Mr McDonnell said the Budget "looks more like a press stunt to hide George Osborne's failures than about any serious policy".
He said: "Take his education announcement, it won't address the real issue in our education system around increasing class sizes, shortage of teachers and lack of school places by just forcing schools to become academies.
"With only one in four schools getting any additional money for the extra hour he's adding to the school day, we will see schools competing with each other for funding and parents will see their aspirations constrained."