Today’s figures for the state of the nation’s finances could scarcely have been worse.

With the costs of the recession into which Britain is now sliding only just starting to pile up, and decisions yet to be taken about how to factor in the bills for the multi-billion pound bailout of the country’s banks, a tide of red ink is already lapping around Alistair Darling’s feet.

Matters will get a whole lot worse in the month’s ahead. The Chancellor is set to be engulfed by further waves of extra borrowing as the toll from economic downturn, as well as from the credit crisis, mounts.

Already borrowing for the first half of the 2008-09 financial year has soared to a record £37.6 billion as the flow of tax revenues into the Treasury starts to run dry.

Mr Darling now has no hope of achieving the £43 billion borrowing total he planned for in his March Budget. The eventual figure will almost certainly be more than £60 billion, and perhaps as high as £70 billion.

In 2010, the combination of weakening tax receipts as the economy stalls, rising welfare bills for lengthening dole queues, and the Chancellor’s plan to bring forward future government spending to try to shore-up growth make £100 billion-plus in borrowing look increasingly inevitable.

What can, or should, Mr Darling do about all this? The answer to both questions is not much.

In an ideal world, the Government would have acted to bolster the public finances several years ago, while the economic good times rolled, providing itself with a cushion for more troubled times. It was cautioned over the need to do so often enough, but failed to act.

All that, though, is history. The Chancellor now has little choice but to let borrowing take the strain as the downturn deepens. To try to curb spending, or restrain borrowing with tax rises now, would be to risk turning a painful recession into a ruinous slump.

The Keynesian “pump-priming” that Mr Darling, intends, bringing forward to this year and next spending that was planned for further ahead, is also a sensible course — though not one without its own difficulties. The sort of capital projects which the Treasury hopes to hasten can be very hard to speed through.

Even when the private sector was in fine fettle and necessary private finance partnerships could easily be secured, the Government was struggling to meet its goals for the infrastructure investment spending. These will be a whole lot tougher to meet now.

Further ahead, the price of the heavy borrowing now needed to avert the worst potential effects of recession will also be high — both for the next Government, and for the taxpayers who will eventually foot the bill.

After the next election, a nasty combination of tax increases and spending restraint will be required once the recession we are now entering has past. This will be as unpalatable to the country as the weaker recovery that, inescapably, it also implies.

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