French economist Thomas Piketty's book on income inequality soared Tuesday to the top of online retailer Amazon's best sellers. Already running in Amazon's top 100 since the English version, "Capital in the Twenty-First Century," was released last month, Piketty's book climbed past hit books like "Frozen", "Game of Thrones" and "Heaven is for Real, which has been on the list from 28 months. Piketty's book has drawn huge interest as US political leaders debate whether widening income disparity is a problem that requires political action. On a trip through Washington last week he met with Treasury Secretary Jacob Lew and the top economic advisors of President Barack Obama in the White House. The 700-page opus has been praised as one of the most important economic works in recent years, using data the past two centuries to argue that the wealthy are hoarding more of an economy's income than ever and that existing policies only mean that will increase. But he has been denounced by American conservatives as a neo-Marxist. A review in the Wall Street Journal branded Piketty a "utopian visionary" whose book "is less a work of economic analysis than a bizarre ideological screed."