The agency’s revenue in the US grew by 54% in the period, during which it opened its fourth US office, in Atlanta. The US accounted for a third of the company’s overall revenue of £9.09m, which was up from £7.2m in the same period last year.

Overall operating profit was up 24% to £628,000.

Business was also strong in Germany and Switzerland, the company said. Revenue in the UK increased only marginally, but the country remains BrainJuicer’s largest source of profit.

Its Dutch business declined by 24% because of falling spending by its major client in the country. “We are endeavouring to build a new client base within the Netherlands, and this is taking time,” the company said.

China and Brazil showed “encouraging early signs”, it said, but are “not yet generating much revenue”.

CEO John Kearon (pictured, with CFO James Geddes) said: “We are delighted to have continued our significant international growth in revenue and profit, all organic, despite these challenging economic times.”

The company said it plans to open an office in Milan later this year, and is on track to meet market expectations for the full year.