Britain faces a “dangerous cocktail” of threats. There is a culture of “creeping complacency” that the economy is problem free. The biggest risk is that people forget about the recession and assume that it is “job done”.

Business leaders who turned up to listen to George Osborne in Cardiff on Thursday could be forgiven for wondering what’s happened to the chancellor who delivered such an upbeat autumn statement six weeks ago.

Then, the talk was of how no country had grown faster than Britain since 2010, of how unemployment was falling in every region, and of how investment was booming. In Wales, the talk was of how all this could be jeopardised by plunging Chinese stock markets, the stand-off between Saudi Arabia and Iran, and by the recessions in Russia and Brazil. Goodbye Tigger; hello Eeyore.

To be fair to the chancellor, he stressed in his autumn statement that Britain still had problems that needed fixing, but the change in tone was far more marked than justified by any recent economic news.

True, the economy’s growth rate in the third quarter of 2015 has been revised down a tad, from 0.5% to 0.4%, and that will probably result in growth for the whole of last year coming in a bit below the autumn statement forecast of 2.4%.

But the growth figures are frequently revised, and there is not a lot of evidence to suggest that the economy has suddenly hit the wall. Retail spending is strong, car sales were at a record level last year and mortgage demand is up.

Chancellors do not normally get too worked up about the ups and downs of global financial markets. The new year has certainly seen big falls in share and commodity prices, and there is a risk – highlighted by the World Bank – of a crisis in emerging markets combining with financial turbulence to create a perfect storm. But the eurozone – a far more important export market for Britain than China, Russia and Brazil combined – has been doing a bit better of late.

It could be that the chancellor has learned a lesson from his experience in the last parliament, when the economy grew much less quickly than expected, and has decided to err on the side of caution. The alternative explanation is that there is a nasty piece of economic news lurking out there that Osborne knows about but we don’t.

In the City, the story doing the rounds was that the bad news will come in the form of a much higher budget deficit for 2015-16 than was forecast in the autumn statement. Borrowing in the first eight months of the financial year was only a couple of billion short of the £69bn predicted for the whole year.

January will be key, because it is the month in which income tax receipts from self-assessment come rolling in to the exchequer. But it will take a really hefty surplus for the chancellor to prevent a borrowing overshoot. Some analysts think the Office for Budget Responsibility, which forecasts the public finances for the government, could be out by as much as £10bn this year.

This would cause a real headache for the chancellor, who has pledged to run a budget surplus by 2019-20 and every year after that. If he is going to be true to his own principles, Osborne would have to raise taxes or cut spending to put the public finances back on track. That, though, would not be wildly popular and it would be as well to have somebody to blame.