Global spillovers from China's slowdown have been “much larger than we could have anticipated,” affecting the global economy through reduced imports and weaker demand for commodities, IMF Economic Counselor Maurice Obstfeld said in an interview posted on the fund's website.

After a year in which China's efforts to contain a stock-market plunge and make its exchange rate more market-based roiled markets, the health of the world's second-biggest economy will again be a key issue to watch in 2016, Obstfeld said.

“Growth below the authorities' official targets could again spook global financial markets,” he said as global equities on Monday got off to a rough start to the year. “Serious challenges to restructuring remain in terms of state-owned enterprise balance-sheet weaknesses, the financial markets, and the general flexibility and rationality of resource allocation.”