The number of millionaires in Asia has overtaken North America for the first time in a sign of wealth shifting across the globe due to the economic downturn, according to a new report.

In the Asia-Pacific region there are now 3.37 million men and women with more than $1m (£635,000) in the bank, compared with 3.35 million in North America, Capgemini and RBC Wealth Management's latest world wealth report revealed.

But the overall level of wealth in North America is still the highest in the world, with its millionaires, such as Warren Buffett and Bill Gates, controlling $11.4tn, while Asian businessmen control $10.7tn – although wealth levels declined twice as fast in North America as in Asia in 2011.