The international spillover effects of US monetary policy uncertainty

•US monetary policy uncertainty (MPU) shocks spillover to international bond yields.•MPU shock impact is over and above conventional first moment effects.•Different mechanisms are at work for advanced vs. emerging countries.•MPU shocks impact advanced and emerging equity markets after the financial crisis. An extensive literature studies the international transmission of US monetary policy surprises (shifts in expected path of the policy rate). In this paper we show that changes in uncertainty around the expected path constitute an important additional dimension of spillover effects to global bond yields. In advanced countries, it is the term premium component of yields that responds to uncertainty. We find that this can be explained by an international portfolio balance mechanism. In contrast, for emerging countries it is the expected component of yields that reacts to uncertainty. This can be rationalized from a flight to safety channel. We find heterogeneity in the country-level response to uncertainty only in emerging countries and it is driven by the degree of financial openness. Finally, equity markets in both advanced and emerging countries also respond to US monetary policy uncertainty.