While the latest borrowing figures [2] aren't quite as bad as expected, they still make grim reading for George Osborne. The August deficit was £14.41bn, the largest figure on record for that month and further evidence that the Chancellor's deficit reduction plan has stalled. Borrowing so far this year (April-August) is £59bn, 22% (£10.6bn) higher than in the same period last year.

The Treasury derived some comfort [3] from the fact that total borrowing for last year (2011/12) was revised down from £126bn to £119.3bn (largely due to an underspend by local government) but this trend almost certainly won't continue. Capital Economics, for instance, expects the government to miss its deficit target for this year (£119.9bn) by £30bn. For the first time since Osborne entered No. 11, borrowing is set rise in annual terms, a significant blow to his political narrative of "balancing the books".

Worse, the parlous state of the public finances means that Osborne will likely be forced to announce the abandonment [4] of his golden debt rule when he delivers his autumn statement on 5 December. Mervyn King, who has a long-standing alliance with Osborne, told Channel 4 News [5] last night that slow growth (or rather, no growth) meant it would be "acceptable" for Osborne to miss the target, which requires public sector debt to be falling as a share of GDP by 2015-16.

While even Osborne recognises that it would be economically reckless to impose deeper cuts in an attempt to meet the rule, its abandonment will cause him much political pain - he will, indisputably, have failed on his own terms.