Alistair Darling spoke to chambers of commerce at Cardiff City's stadium
Chancellor Alistair Darling has warned of "hard choices" in public spending to tackle soaring government debt.
In a speech to business leaders in Cardiff he said he "won't flinch from difficult decisions".
It follows his well-publicised dispute with Gordon Brown over whether to announce deeper cuts in departments' budgets before the general election.
Mr Darling stopped short of announcing what services would be cut but said he plans to halve the debt in four years.
He made clear that even sacred cows such as the NHS will be expected to make a contribution to efficiency savings, citing a drive to make better use of preventative care to avoid the development of long-term conditions which are expensive to treat.
Alistair Darling has said the economy still had a long way to go before recovering
The government's "first priority" in seeking to bring spending under control would be efficiency savings and shifting resources to the front line, rather than reductions in services, he said.
Earlier, Mr Darling told BBC Radio Wales: "What I'm saying today is that I think the Government can make a difference.
"It also means there are some areas where you might not be able to do everything you want to do today, you might have to do that further down the line."
Government action meant people losing their jobs during the recession were returning to work quickly, unlike the 1980s and '90s when the unemployed were "left to get on with it".
He added: "This isn't some sort of political game. The decisions we take over the next year or so will define the shape of Wales, the United Kingdom, for the next decade and beyond.
"What I want to see is a serious debate in this country as to where we need to spend our money, where we need to set our priorities which will define us, as a country, which will provide will provide people with jobs and opportunities for the next five or 10 years.
"That is a very important discussion to have. There will come a time when you have to spell out 'well, this is what we're doing, this is what we're not doing'.
"But at this stage what I'm trying to do is get a far wider debate on what is it, as a country, we need to concentrate on that will define us for the next generation."
Mr Darling is in the city to deliver the Callaghan Lecture, in honour of former prime minister James Callaghan, at the Cardiff City Stadium.
The details of Mr Darling's plans will be formally announced in this autumn's pre-Budget report.
On Sunday, Treasury Minister Liam Byrne insisted it was possible to halve the budget deficit while managing to "protect public services".
He said economic stimulus measures would continue next year but the focus would switch to paying off the debt.
Mr Byrne told the BBC: "In the pre-Budget report we will set out in more detail how we will halve the deficit over four years and protect those public services which we think are key to helping people make the most of the future in this country".
Mr Brown and Mr Darling are reported to have had lengthy discussions over the summer on the new, tougher public spending strategy.
The issue is expected to be central to the main political parties' general election campaigns.
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