Switzerland rose on the quality of its business environment and the United States slipped on concerns about public finances.

Switzerland, which had been ranked fourth in the 2005 edition of the elite think tank's competitiveness index, climbed into the top position thanks to factors including its public institutions and scientific research, the WEF said.

The United States still received high marks for innovation, but dropped into sixth place because of growing threats posed by macroeconomic imbalances, particularly rising levels of public debt associated with repeated fiscal deficits, said the WEF.