At the time, more than half of those polled thought the US would remain the world's top economic powerhouse for the following 20 years.

 

The survey comes amid economic uncertainty in the US, shaken by turbulence in financial markets, a weak dollar and continuing worries over the fallout from the sub-prime mortgage crisis.

 

China's economy, meanwhile, continues to enjoy record growth.

 

Last month the country's National Statistics Bureau said GDP growth for 2007 stood at 11.4 per cent – the fastest in 13 years and the fifth year in a row that growth had topped 10 per cent.

 

According to the latest annual statistics from the World Bank, the US stood as the world biggest economy with a GDP of $13.2 trillion in 2006.

 

That compares with China which had a GDP of just under $2.7 trillion in the same year.

 

Japan and Germany were the world's second and third largest, with GDPs or $4.34 trillion and $2.9 trillion respectively, according to the World Bank.

 

The Gallup World Affairs Survey was conducted from February 11-14 and involved telephone interviews with 1,007 adults in the US with a margin of error of plus or minus three percentage points.