FTSE 250 firm Hays' today revealed UK revenues fell by 10 per cent in the six months to December.
"Immediately post the EU referendum we had a couple of weeks were activity levels dropped quite markedly," Alistair Cox, the chief executive of Hays, told City A.M.
The 55-year-old said although the London market was hit hardest, with revenues down 15 per cent, other parts of the country had fared much better. Scotland and Northern Ireland figures were broadly flat, while in Wales they were down two or three per cent.
Living in London we can sometimes get carried away with how good and bad things feel, based on what we see.
"London does tend to be a bit of an exaggerated market. When things are good, London is really good. When things are more difficult, London can feel really difficult. And that's what we are witnessing today. As we live and work in London sometimes it can feel like the whole world is talking about the implications of Brexit and how difficult this is going to be.
But when you go out the Midlands, the north, you go out west, Scotland, Northern Ireland people are getting on with things.
Cox was referring to the private sector side of Hays UK business, which represents 75 per cent of operations. He said public sector hiring remained extremely challenging given the current government's tightening of the purse strings.
Although the firm started out in the UK, Hays now generates 75 per cent of its earnings from abroad, and Cox was keen to emphasise the group's headline 17 per cent revenue growth and 10 per cent increase in operating. "We're in rude health," he said.
"Virtually every market around the world is growing, most of them in double-digits."
He said: "I never personally try to look at the share price on the day of results."