“The public finance situation in the U.S. is worse than Europe. In Europe the leaders are cornered to do reforms. However, in the U.S., for the past one and a half years, there have been zero reforms in the area of public finance,” Li, currently a professor at Tsinghua University in Beijing, told CNBC on the sidelines of the World Economic Forum in the Chinese port city of Tianjin.

His comments follow a warning by ratings agency Moody's on Tuesday, which said the U.S. could lose its triple-A debt rating if next year's government budget talks do not yield policies that reduce the country's debt.

A mix of U.S. tax hikes and spending cuts - referred to as the "fiscal cliff" - are also set to come into force in January unless lawmakers reach a compromise for avoiding them.

Political deadlock over reducing the unsustainable federal government budget deficit - projected to hit $1.1 trillion this year - prompted Standard & Poor's to downgrade the country's credit rating by one notch to AA+ from AAA in August 2011.