Britain’s Treasury chief is set to warn today of a “dangerous cocktail” of new threats to the economy, insisting that the country is not immune to troubles from abroad.

George Osborne will use a speech to underscore his fears about what he described as “creeping complacency” in the debate about the national economy. In remarks released in advance, he cites a drop in global stock markets and commodity prices, as well as the slowdown in China among the issues buffeting the world economy.

“Last year was the worst for global growth since the crash and this year opens with a dangerous cocktail of new threats,” Osborne said. “For Britain, the only antidote to that is confronting complacency and sticking to the course we’ve charted.”

Britain’s economy is one of the best-performing in the developed world and has expanded for 11 quarters in a row. It grew by 0.4 per cent in the third quarter compared with the previous three-month period.

But in his remarks, Osborne expressed concern that the economy would fall down on the list of everyday concerns.

“Anyone who thinks it’s mission accomplished with the British economy is making a grave mistake,” he is to say.