Sheets steps in from the Federal Reserve Board in Washington DC where he was director of the division of international finance. He also previously acted as the Fed chairman's international advisor at the onset of the European financial crisis in 2010. 

In this new capacity, Sheets will be based in New York, reporting jointly to Willem Buiter, Citi's chief economist, and Andrew Pitt, global head of investment research. He will be working closely with a team of international economists with a focus on the US' position in the global economy. 

The firm said Sheets' background was instrumental in his hire, citing mounting uncertainty over the state of the American financial system and the fact that investors seem to be moving away from what used to be a powerhouse region and into Asia. He brings over 18 years of experience with the Federal Reserve.