George Osborne saved one of the biggest surprises of his spending review to the final moments.

Despite speculation about double digit cuts to police budgets, and an expectation that thousands of jobs would have to be slashed, he revealed that there would be no cuts at all.

"The police protect us and we are going to protect the police" he said.

That's in contrast to the recent rhetoric of the Home Secretary, Theresa May.

Earlier this year, she told the Police Federation to stop "crying wolf" about the impact of cuts. She pointed out that crime figures had fallen - despite cuts to police budgets.

Her combative tone led to the assumption that the 'savings' would continue.

Two officers told me this morning that their colleagues were braced for cuts of as much as 40 per cent.

With extra funds for defence and intelligence guaranteed, it seemed like a sensible conclusion.

But no one saw what was coming. Chief constables, meeting in Manchester, were said to be 'aghast'.

Theresa May has previously taken a 'combative' tone with the Police Federation Credit: PA

The Guardian's crime correspondent Vikram Dodd tweeted: "One police chief on no cuts to police budget: 'I'm just getting off the floor'.

Later, one Scotland Yard officer tweeted: "In two words... very relieved".

Though perhaps 'relieved' is an understatement. Even the most optimistic insiders were expecting reductions of more than 10 per cent.

The context to today's announcement is what happened in Paris.

With the possibility of a marauding attack by gunmen considered to be an increasing threat in the UK, thinning the blue line would have been politically difficult for the government.

Instead, extra money will be made available for the training of firearms officers.

Analysts had expected huge cuts to police

There are some important points to remember though.

It might be up to elected Police and Crime Commissioners to raise council tax to ensure that spending stays in line with inflation.

Pressure on police budgets won't simply disappear.

And add to that the growing threat of online crime, which is expensive to fight.

Perhaps the big changes to policing which appeared to be around the corner - such as mergers between forces to trim back offices - have been delayed, rather than scrapped.